Article 52

Resolution relating to the Declaration on the prohibition of military, political or economic coercion in the conclusion of treaties

The United Nations Conference on the Law of Treaties,

Having adopted the Declaration on the prohibition of military, political or economic coercion in the conclusion of treaties as part of the Final Act of the Conference,

1.Requests the Secretary-General of the United Nations to bring the Declaration to the attention of all Member States and other States participating in the conference, and of the principle organs of the United Nations;

2.Requests Member States to give the Declaration the widest possible publicity and dissemination.

Materials:

Proposal by Afghanistan: OR 1969 Plenary 100, para. 3.

Minutes: OR 1968 CoW; OR 1969 Plenary 93, para. 5 f, 100 f, para. 1 , 168 f, para. 1 .

Vienna Conference Vote: 99:0:4

Selected Literature: see the literature mentioned in Article 52.

The basis of this commentary was prepared by Alison Wiebalck.

1OR 1969 Plenary 100, para. 2 (“the purpose of which was to provide an organic link for the draft declaration”); statement by the delegation of Japan, ibid. 101, para. 10

(“designed to secure wider publicity and dissemination for the declaration”).

2 E.g., the statements by the delegations of Brazil, ibid. 101, para. 11; then Czechoslovakia, ibid. para. 13; and the Netherlands, ibid. 101 f, para. 18. The vote is at ibid. 101, para. 13.

3 Statement in Vienna by the delegation of Afghanistan, ibid. 100, para. 2.

Article 53

Treaties conflicting with a peremptory norm of general international law ( jus cogens)

A treaty is void if, at the time of its conclusion, it conflicts with a peremptory norm of general international law. For the purposes of the present Convention, a peremptory norm of general international law is a norm accepted and recognised by the international community of States as a whole as a norm from which no derogation is permitted and which can be modified only by a subsequent norm of general international law having the same character.

Article 53 Traités en conflit avec une norme impérative du droit international général (jus cogens)

Est nul tout traité qui, au moment de sa conclusion, est en conflit avec une norme impérative du droit international général. Aux fins de la présente Convention, une norme impérative du droit international général est une norme acceptée et reconnue par la communauté internationale des Etats dans son ensemble en tant que norme à laquelle aucune dérogation n’est permise et qui ne peut être modifiée que par une nouvelle norme du droit international général ayant le même caractère.

Artikel 53 Verträge im Widerspruch zu einer zwingenden Norm des allgemeinen Völkerrechts (ius cogens)

Ein Vertrag ist nichtig, wenn er im Zeitpunkt seines Abschlusses im Widerspruch zu einer zwingenden Norm des allgemeinen Völkerrechts steht. Im Sinne dieses Übereinkommens ist eine zwingende Norm des allgemeinen Völkerrechts eine Norm, die von der internationalen Staatengemeinschaft in ihrer Gesamtheit angenommen und anerkannt wird als eine Norm, von der nicht abgewichen werden darf und die nur durch eine spätere Norm des allgemeinen Völkerrechts derselben Rechtsnatur geändert werden kann.

ILC Draft 1966

Article 50—Treaties conflicting with a peremptory norm of general international law ( jus cogens)

A treaty is void if it conflicts with a peremptory norm of general international law from which no derogation is permitted and which can be modified only by a subsequent norm of general international law having the same character.

Materials:

Waldock Report II: Articles 1 and 13.

Minutes: YBILC 1963 I 2 f, 62 , 213 , 291 f, 314 f, 317.

ILC Draft 1963: Article 37.

Waldock Report V: Article 37.

Minutes: YBILC 1966 I/1 36 , 121 f; YBILC 1966 I/2 309 f, 331.

ILC Draft 1966: Article 50.

Minutes: OR 1968 CoW 293 , 306 , 321 f, 330 , 471 ; OR 1969 Plenary 84, 93 , 102 .

Vienna Conference Vote: 87:8:12

Selected Literature:

A-C

L.A. Alexidze, Legal Nature of jus cogens in Contemporary International Law, RC 172 (1981 III) 219 ; R.J. Araujo, Anti-Personnel Mines and Peremptory Norms of International Law: Argument and Catalyst, Vanderbilt JTL 30 (1997) 1 ; E.C. Baptista, Jus cogens em Direito internacional (1997); A. Bernardini, Qualche riflessione su norme internazionale di jus cogens e giurisdizione della Corte nella Convenzione di Vienna sul diritto dei trattati, in: Studi G. Morelli (1975) 81 ; M. Byers, Conceptualizing the Relationship Between jus cogens and erga omnes Rules, Nordisk TLR 66 (1997) 211 ; J.H. Castro Villalobos, La norma de jus cogens en el derecho internacional (1981); J.I. Charney, Universal International Law, AJIL 87 (1993) 529 ; G.A. Christenson, Jus cogens: Guarding Interests Fundamental to International Society, Virginia JIL 28 (1988) 585 ; Id., T he World Court and jus cogens, AJIL 81 (1987) 93 ; W. Czaplinski, Concepts of jus cogens and Obligations erga omnes in International Law in the Light of Recent Developments, Polish YBIL 23 (1997/1998), 87 ; Id., Jus cogens and the Law of Treaties, in: Ch. Tomuschat/J.-M. Thouvenin (eds.), The Fundamental Rules of the International Legal Order. Jus cogens and Obligations erga omnes (2006) 83 .

D-G

A.A. d’Amato, It’s a Bird, It’s a Plane, It’s jus cogens, Connecticut JIL 6 (1990) 1 ; G.M. Danilenko, International jus cogens. Issues of Law-Making, EJIL 2 (1991) 42 ; F. de Visscher, Positivisme et jus cogens, RGDIP 75 (1971) 5 ; F. Domb, Jus cogens and Human Rights, Israel YBHR 6 (1976) 104 ; Z. Drnes de Clément, Las normas imperativas de derecho internacional general (jus cogens), in: Estudios de derecho internacional en homenaje al profesor E.J. Rey Caro (2002) I 647 ; M. Fahrni, Peremptory

Norms as General Rules of International Law, ÖZöR 22 (1971) 383 ; Ch.A. Ford, Adjudicating jus cogens, Wisconsin ILJ 13 (1994) 145 ; M. Frei, Von einem liberalen zu einem konstruktivistischen Völkerrechtsverständnis. Ein Versuch am Beispiel des ius cogens (2007); G. Gaija, Jus cogens beyond the Vienna Convention, RC 172 (1981 III) 271 ; M.J. Glennon, Peremptory Nonsense, in: St. Breitenmoser et al. (eds.), Human Rights, Democracy and the Rule of Law. Liber amicorum L. Wildhaber (2006), 1265; N. Greenwood Onuf/R.K. Birney, Peremptory Norms of International Law: Their Source, Function and Future, Denver JILP 4 (1974) 187 ; A. Gomes Robledo, Le jus cogens international: sa genèse, sa nature, ses fonctions, RC 172 (1981 III) 9 .

H-K

L. Hannikainen, Peremptory Norms (jus cogens) in International Law. Historical Development, Criteria, Present Status (1988); A.J. Hoogh, The Relationship Between jus cogens, Obligations erga omnes and International Crimes: Peremptory Norms in Perspective, Austrian JPIL 42 (1991) 183 ; P. Hulsroj, Jus cogens and Disarmament, IJIL 46 (2006) 1 ; St. Kadelbach, Jus cogens, Obligations erga omnes and Other Rules—The Identification of Fundamental Norms, in: Ch. Tomuschat/J.-M. Thouvenin (eds.), The Fundamental Rules of the International Legal Order. Jus cogens and Obligations erga omnes (2006). 21 ; Id., Zwingendes Völkerrecht (1992); J. Kasto/K. Kwik, Jus cogens and Humanitarian Law (1994); E. Klein, Menschenrechte und Ius cogens, in: J. Bröhmer et al. (eds.), Internationale Gemeinschaft und Menschenrechte. Festschrift für G. Ress (2005) 151 : R. Kolb, Jus cogens, intangibilité, transgressibilité, derogation “positive” et “negative”, RGDIP 109 (2005) 305 ; Id., The Formal Source of jus cogens in Public International Law, ÖZVR 53 (1998), 69 ; Id., Théorie du jus cogens international, Revue Belge 36 (2003) 5 ; Id., Théorie du jus cogens international. Essai de relecture du concept (2001); E. Kornicker, Jus cogens und Umweltrecht: Kriterien, Quellen und Rechtsfolgen zwingender Völkerrechtsnormen und deren Anwendung auf das Umweltvölkerrecht (1997).

L-M

J. Lador-Lederer, “Victims’ Law”, jus cogens and Natural Law, IsraelYBHR 8 (1978) 267 ; A.J. Leonetti, Interprétation des traités et règles impératives du droit international général ( jus cogens), ÖZöR 24 (1973) 91 ; R.St.J. Macdonald, The Charter of the United Nations and the Development of Fundamental Principles of International Law, in: B. Cheng/E.D. Brown (eds.), Contemporary Problems of International Law: Essays in Honour of G. Schwarzenberger (1988) 196 ; M.M. Magallona, The Concept of jus cogens in the Vienna Convention on the Law of Treaties, Philippine LJ 51 (1976) 521 ; F.A. Mann, The Doctrine of jus cogens in International Law, in: Festschrift U. Scheuner (1973) 399 ; K. Marek, Contribution à l’étude du jus cogens en droit international, in: Recueil d’études de droit international en homage à P. Guggenheim (1968) 428 ; L. McGregor, State Immunity and jus cogens, ICLQ 55 (2006) 437 ; H. Mosler, Jus cogens im Völkerrecht, SJIR 25 (1968) 9 .

N-P

V. Nageswar Rao, Jus cogens and the Vienna Convention on the Law of Treaties, IJIL 14 (1974) 362 ; J. Nisot, Le “jus cogens” et la Convention de Vienne sur les traités, RGDIP 76 (1972) 692 ; St. Oeter, Jus cogens und der Schutz der Menschenrechte, in: St. Breitenmoser et al. (eds.), Human Rights, Democracy and the Rule of Law. Liber amicorum L. Wildhaber (2006), 499 ; A. Orakhelashvili, Peremptory Norms in International Law (2006); Id., The Impact of Peremptory Norms on the Interpretation and Application of United Nations Security Council Resolutions, EJIL 16 (2005) 59 ; A.J. Poblador, The Military Bases and Mutual Security Agreements in the Lights of the Doctrines of jus cogens and rebus sic stantibus, Philippine LJ 51 (1976) 264 ;

K. Parker/L.B. Neylon, Jus cogens: Compelling the Law of Human Rights, Hastings ICLR 12 (1989) 411 ; V. Paul, The Legal Consequences of Conflict Between a Treaty and Imperative Norms of General International Law (jus cogens), ÖZöR 21 (1971) 19 ; A.L. Paulus, Jus cogens in a Time of Hegemony and Fragmentation: An Attempt at a Re-appraisal, Nordic JIL 74 (2005) 297 ; J. Paust, The Reality of jus cogens, Connecticut JIL 7 (1991) 81 .

R

M. Ragazzi, The Concept of International Obligations erga omnes (1997); H.B. Reimann, Jus cogens im Völkerrecht. Eine quellenkritische Untersuchung (1971); W. Riphagen, From Soft Law to jus cogens and Back, Victoria University of Wellington Law Review 17 (1987) 81 ; N. Ronzitti, La disciplina dello jus cogens nella Convenzione di Vienna sul diritto dei trattati, Communicazioni e studi 15 (1978) 241 ; Id., Trattati contrari a norme imperative del diritto internazionale?, in: Studi in onore di G. Sperduti (1984) 209 ; Ch.R. Rozakis, The Concept of jus cogens in the Law of Treaties (1976); A.P. Rubin, Actio popularis, jus cogens and O enses erga omnes? New England Law Review 35 (2001) 265 ; U. Rumpf, Zur Lehre von den “zwingenden Völkerrechtsnormen”, in: G. Brunner et al. (eds.), Sowjetsystem und Ostrecht. Festschrift für B. Meissner (1985) 561 .

S

U. Scheuner, Conflict of Treaty Provisions with a Peremptory Norm of General International Law and its Consequences, ZaöRV 27 (1967) 520 ; G. Schwarzenberger, International jus cogens? Texas LR 43 (1965) 455 ; E. Schwelb, Some Aspects of International jus cogens as Formulated by the International Law Commission, AJIL 61 (1967) 946 ; I. Scobbi, The Invocation of Responsibility for the Breach of “Obligations under Peremptory Norms of General International Law”, EJIL 13 (2002) 1201 ; D. Shelton, Normative Hierarchy in International Law, AJIL 100 (2006) 291 ; B. Simma/Ph. Alston, The Sources of Human Rights Law, Custom, jus cogens and General Principles, Australian YBIL 12 (1992) 82 ; E. Suy, Article 53, in: Corten/Klein (eds.) 1905 ; J. Sztucki, Jus cogens and the Vienna Convention on the Law of Treaties (1974).

T-W

Ch.J. Tams, Schwierigkeiten mit dem jus cogens, AVR 40 (2002) 331 ; P. Tavernier, L’identification des règles fondamentaux—un problème résolu, in: Ch. Tomuschat/J.-M. Thouvenin (eds.), The Fundamental Rules of the International Legal Order. Jus cogens and Obligations erga omnes (2006) 1 ; P. Terz, Zum jus cogens im demokratischen Völkerrecht, Staat und Recht 7 (1978) 617 ; Ch. Tomuschat/J.-M. Thouvenin (eds.), The Fundamental Rules of the International Legal Order. Jus cogens and Obligations erga omnes (2006); A. Verdross, Jus dispositivum and jus cogens in International Law, AJIL 60 (1966) 55 ; J. Verhoeven, Jus cogens and Reservations or “Counter-Reservations” to the Jurisdiction of the International Court of Justice, in: K. Wellens (ed.), International Law: Theory and Practice. Essays in Honour of E. Suy (1998) 195 ; M.M. Whiteman, Jus cogens in International Law, with a Projected List, Georgia JICL 7 (1977) 609 ; K. Zemanek, How to Identify Peremptory Norms of International Law, in: P.-M. Dupuy et al., (eds.), Völkerrecht als Wertordnung. Common Values in International Law, Essays in Honour of Ch. Tomuschat (2006) 1103 .

means of a treaty abrogate inter se any rules of customary international law.3 Nevertheless, the 1919 League of Nations Covenant,4 the 1928 Kel- logg-Briand Pact and, since 1945, Article 2, para. 4 of the UN Charter all limited peremptorily the use of force in international law (Article 52, q.v., N. 1). Since 1945 a certain consensus has arisen in legal doctrine on the existence of such peremptory norms5 spurring debate on which rules have the character of jus cogens, their legal basis and position within the sources of international law, and, in particular, the e ects of jus cogens on treaties.6

2. History

2In 1953 Lauterpacht envisaged a concept of “overriding principles of international law”.7 Fitzmaurice Report III stipulated that “a treaty . . . should be in conformity with . . . those . . . rules of international law which [were] in the nature of jus cogens”.8 The topic was taken up again in Waldock Report II of 1963 which contained the nucleus of the structure of today’s Article 53.9 Topics for discussion in the ILC in 1963 were whether norms of jus cogens existed; their retroactivity; the position of Article 53 in the Convention; and the separability of treaty provisions conflicting with norms of jus cogens.10 While ILC members generally accepted the concept, there was some confusion as to the position of jus cogens in the context of sources.11 The ILC adopted its 1963 draft unanimously.12 In their comments on the

5ILC Report 1966, YBILC 1966 II 247, para. 1; McNair, Law of Treaties 213 (“[i]t is di cult to imagine any society, whether of individuals or of States, whose law sets no limit whatever to freedom of contract”); contra Schwarzenberger, Texas LR 43 (1965) 476 (“international law . . . fails to bear out any claim for the existence of international jus cogens”). See also the title of Glennon’s contribution to the Liber amicorum

Wildhaber: “Peremptory Nonsense”, ibid. 1265 .

6 See the summary in Sinclair, Vienna Convention 207 .

7YBILC 1953 II 106; also ibid. 93 (“[a] treaty . . . is void if its performance involves an act which is illegal under international law”). On the history of Article 53, see Gómez

Robledo, RC 172 (1981 III) 37 ; Kadelbach, Zwingendes Völkerrecht 36 . 8 YBILC 1958 II 26.

9 Article 1 in YBILC 1963 II 29; also Article 13 with examples, ibid. 52.

10YBILC 1963 I 2 f, 62 , 213 , 291 f, 314 f, and 317. See the statement by Tunkin, ibid. 69, para. 20 (“he hoped to resist the temptation to engage in a theoretical discussion”).

11See, e.g., the statement by Rosenne, ibid. 74, para. 12, cited in N. 6.

12Ibid. 215, para. 89.

whereas it found much support with African, Asian and Southern American States as well as the former communist States.22 Eventually, a compromise was reached whereby the acceptance of the system of compulsory judicial settlement in Article 66, para. (a) (q.v., N. 6–9) assured adoption of Article 53.23

13Waldock Report V, YBILC 1966 II 23, para. 1.

14Texas LR 43 (1965) 455 ; see the reply to this article by Verdross, AJIL 60 (1966) 55 , and in YBILC 1966 I/1 37.

15YBILC 1966 I/1 121, para. 129; Briggs abstained, Reuter voted against, ibid. paras. 124, 130.

16At one stage, the voting threatened to get out of hand, OR 1968 CoW 331 . The debates are recorded at OR 1968 CoW 293 , 306 , 321 f, 330 , and 471 .

17See the summary by Elias, RC 134 (1971 III) 394; Rozakis, Concept 49 n. 9 (“great number of outstanding problems that the ILC had left unresolved in its draft articles on jus cogens”).

18Statement by the delegation of the then USSR, OR 1968 CoW 294, para. 4.

19Statement by the French delegation, ibid. 309, para. 30; see also the statements by the delegations of Turkey, ibid. 300, para. 8 (“opened the door to all kinds of abuse”); and the UK, ibid. 330, para. 32 (“Pandora’s box”), and 304, para. 54 (“[Article 53] would be at the mercy of unilateral assertions and counter-assertions made by the States concerned”).

20See the statement by the Expert Consultant, Sir Humphrey Waldock, ibid. 328, para. 80.

21OR 1969 Plenary 84, 93 , 102 .

22Frowein, EPIL 3 (1997) 66. Western States feared, in the words of the French delegation, that “a majority [of States] could bring into existence peremptory norms that would be valid erga omnes”, OR 1969 Plenary 94, para. 17.

23Frowein, ibid.

In 1969 the words “accepted and recognised by the international community of States as a whole” were added, as was a US amendment which included “at the time of its conclusion”.24 In the final vote, Article 53 was adopted by 87 votes to eight, with twelve abstentions, the vote being taken by roll-call.25 France eventually voted against the Convention, inter alia, on account of the provisions on jus cogens.26

B. INTERPRETATION OF ARTICLE 53

1. Scope

5“[ Jus cogens] is a term which is well enough understood, but is not easily defined with precision”.27 Article 53 is divided into two sentences. The first sentence sets out the rule, namely that peremptory norms allow for no contradiction by treaties (N. 20–21); while the second sentence defines a peremptory norm of general international law for the purposes of the Convention (N. 8–19).28 As such, Article 53 provides a comparatively simple statement of the principle.29

6Peremptory norms have to be distinguished from other concepts of international law:30

–the obligatory or binding nature is not a typical quality of jus cogens. It pertains to all rules of customary international law as well as to all treaty norms. The fact that conventional or customary rules may be amended, terminated or even breached, does not call in question their binding nature;31

–a peremptory rule of international law di ers from Article 103 of the UN Charter and Article 30 of the Convention (q.v., N. 9–10) in that these provisions provide conflict clauses which take no stand on the invalidity of a conflicting treaty;32

24OR Documents 174, subpara. 462(i)(b).

25Against: Australia, Belgium, France, Liechtenstein, Luxembourg, Monaco, Switzerland, and Turkey. Abstaining: Gabon, Ireland, Japan, Malaysia, Malta, New Zealand, Norway, Portugal, Senegal, South Africa, Tunisia, and United Kingdom; OR 1969 Plenary 106 f, para. 65.

26See the statement of the French delegation (“no one would be surprised”); on the French position generally, see Villiger, Customary International Law N. 456.

27Waldock Report II, YBILC 1963 II 39, para. 2.

28See the statement in Vienna by Yasseen, Chairman of the Drafting Committee, OR 1968 CoW 471, para. 5.

29ILC Report 1966, YBILC 1966 II 248, para. 4.

30On this, ibid. para. 2; Domb, IsraelYBHR 6 (1976) 112, 114.

31Verdross/Simma N. 528; statement by Yasseen in the ILC, YBILC 1966 I/1 90, para. 69. See the apparent misunderstanding by Rosenne, ibid. 74, para. 12 (“he was not . . . prepared to say that every [UN] General Assembly resolution, even those which constituted declarations, had per se the character of jus cogens”).

32Sztucki, Jus cogens 97; Waldock Report V, YBILC 1966 II 24, para. 3.

–a treaty provision does not become peremptory by the mere fact that it contains a rule stating that no derogation is permitted. In case of a breach of such a rule by a subsequent treaty, the latter will not be void. However, Articles 30 or 60 (q.v.) may apply;33

–erga omnes norms are “obligations of a State towards the international community as a whole”.34 With this e ect, erga omnes norms certainly comprise all peremptory norms, but go beyond jus cogens in that they do not invalidate conflicting treaties.

of the present Convention, though in fact the provision is widely considered as providing a general statement on the conditions and e ects of jus cogens.38 Thus, a peremptory norm of general international law is defined in Article 53 as a norm accepted and recognised by the international community of States as a whole as a norm from which no derogation is permitted and which can be modified only by a subsequent norm of general international law having the same character. It transpires that Article 53 lists altogether four conditions for a norm to be peremptory (N. 9–16).39 These are formal, not substantive conditions. In other words, Article 53 does not circumscribe any particular peremptory rules (N. 17); it o ers solely a general definition on the coming about, existence, modification and termination of jus cogens.

33Domb, IsraelYBHR 6 (1976) 114.

34Barcelona Traction Case, ICJ Reports 1970 32, para. 34; Frowein, Obligations erga omnes, EPIL 3 (1997) 757 f; Ragazzi, Concept passim; Kadelbach, Zwingendes Völkerrecht 36 .

35Statement by Rosenne in the ILC, YBILC 1966 I/1 89, para. 63; do Nascimento e Silva, RC 154 (1977 I) 283 .

36Waldock in the ILC, YBILC 1963 I 78, para. 47; also Waldock Report V, YBILC 1966 II 24, para. 4; the ILC Report 1966, YBILC 1966 II 248 f, para. 6.

37Delbrück/Wolfrum III 712; Rozakis, Concept 40 f.

38See, e.g., the treatment of the subject by Frowein, EPIL 3 (1997) 66.

39Delbrück/Wolfrum III 708. Zemanek, Essays Tomuschat 1105, sees only “two vague instructions“ as to the identification of jus cogens in Article 53.

a) Rule of General International Law

9As a fi rst condition, Article 53 requires that jus cogens shall pertain to general international law. Thus, peremptory norms are not a new, or separate, source of law. Rather, they are general and abstract norms40 either of general customary international law or of multilateral conventions within the framework of Article 38, para. 1 of the ICJ-Statute.41 In either case, the rule emerges from the practice of States.42

Given the di culty of conventions acquiring the necessary quasi-universal membership (N. 12), treaties are less suitable for establishing jus cogens. The general binding character of customary international law makes it the most appropriate vehicle for peremptory norms. A distinction is actually unnecessary, since a convention with quasi-universal membership will most likely also be declaratory of customary international law.43

b) No Derogation

10Second, no derogation is permitted from a peremptory norm (except by a subsequent peremptory norm, N. 15). The State community as a whole wishes these norms to have an overriding, peremptory e ect in the entire legal order (N. 11). It may be noted that Article 53 does not distinguish between the particular norms and acts—customary or conventional, multi-, bior unilateral, general or individual, abstract or concrete, etc.—or even principles and situations which might conflict with the peremptory norm. It is simply stated that any derogation is excluded.44 Now, the first sentence regulates the consequence of one type of conflicting norm, i.e., of a treaty

40Villiger, Customary International Law N. 274 f; Domb, IsraelYBHR 6 (1976) 107 .

41Statement in Vienna by Nahlik of the Polish delegation, OR 1968 CoW 302, para. 34; Rozakis, Concept 57. But see the diss. op. of Judge Lauterpacht in the Application of the Convention on the Prevention and Punishment of the Crime of Genocide (Bosnia and Herzegovina v. Yugoslavia) Case, ICJ Reports 1990, para. 100 (“jus cogens operates as a concept superior to both customary international law and treaty”); Whiteman, Georgia JICL 7 (1977) 609 (“jus cogens takes precedence . . . over customary and conventional international law”). On general principles of law, see Bleckmann, Völkerrecht N. 304a.

42Statement in Vienna by the Brazilian delegation, OR 1968 CoW 317, para. 22.

43Villiger, Customary International Law N. 245 . See also the statements in Vienna by the delegations of Italy, OR 1969 Plenary 104, para. 38 (“the rules of jus cogens were essentially customary rules”); and Trinidad and Tobago, OR 1968 CoW 327, para. 63 (“primarily a rule of customary international law”); furthermore the US Court of Appeals in Siderman de Blake et al. v. Argentina et al., ILR 103 (1996) 471 (“jus cogens and customary international law are related”); the UK Court of Appeal in Al-Adsani v. Government of Kuwait et al., BYBIL 67 (1996) 540 (“[i]t is also widely accepted that jus cogens rules are rules of customary international law”); Reuter, Introduction N. 221 f. Ragazzi, Concept 53; contra Rozakis, Concept 73; Weil, AJIL 77 (1983) 438.

44T he ILC mentioned this point in its commentary to the later Article 64, rather than Article 53; see the ILC Report 1966, YBILC 1966 II 261, para. 1.

cerns in particular specially a ected States and the remaining States tacitly accept.49

Today, di culties of ascertaining such practice are mitigated in the framework of the UN and of diplomatic conferences where every State has the possibility of

45Statement by Yasseen of the Iraqi delegation, OR 1968 CoW 295, para. 21 (“[Article 53] did not purport to deal with the whole broad problem of the rule of jus cogens”). See the scope referred to by the International Criminal Tribunal for the Former Yugoslavia in the case of Prosectuor v. Furundzija, ILR 121 (2002) 261, para. 155 (“torture . . . serves to internationally de-legitimize any legislative, administrative or judicial act authorizing torture”). For Bleckmann, Völkerrecht N. 304, Article 53 also renders void unilateral acts.

46See the statement in Vienna by Yasseen, Chairman of the Drafting Committee, OR 1968 CoW 471, para. 4; Gaja, RC 172 (1981 III) 284; Ragazzi, Concept 53.

47Sztucki, Jus cogens 97 . At the Vienna Conference, the US delegation unsuccessfully proposed an amendment according to which the jus cogens rule had to be “recognized in common by the national and regional legal systems of the world”, OR Documents 174, subparas. 462(i) and (ii).

48Delbrück/Wolfrum III 710.

49Villiger, Customary International Law N. 15 .

expressing its opinion and in particular of demonstrating its acceptance of a rule (Issues of Customary International Law, N. 4).50

14In a legal order enshrining the equality of States, the possibility must exist of States opting out from, and persistently objecting to, the rule at its inception (Issues of Customary International Law, N. 8–10). Given the requirement of the acceptance of the international community as a whole, there would, therefore, appear to be room left at most for some few States refusing to accept the jus cogens rule from the outset, and their stance might even be tacitly supported by a small number of other States.51 Once the jus cogens rule has become firmly established, it will become increasingly di cult to maintain the position of persistent objector which may no longer be understood by other States.52 Subsequent objectors, on the other hand, disagreeing with the rule after its inception, remain bound by the rule of jus cogens. Their dissent may amount to a breach of the rule and entail international responsibility.53

In arguing against the possibility of persistent objectors to jus cogens, reference has been made to the example of the former South African régime which was not recognised as a persistent objector to the prohibition of apartheid.54 However, the prohibition of apartheid is part and parcel of the prohibitions of discrimination and degrading treatment both of which appear to have developed qua customary law (and, possibly, qua jus cogens) before apartheid commenced being practised (1950). The former South African regime was, therefore, a subsequent objector still bound by the various rules.

d) Modification by a Rule of Same Character

15Fourth and finally, the peremptory norm can be modified only by a subsequent norm of general international law having the same character. Thus, Article 53 proceeds from a dynamic notion of jus cogens. Law is not immutable, jus cogens may equally be modified (and terminated)—albeit

50Ibid. N. 20 .

51See the statement in Vienna by Yasseen, Chairman of the Drafting Committee in Vienna, OR 1968 CoW 472, para. 12 (“if one State in isolation refused to accept the peremptory character of a rule . . . the acceptance . . . of the rule by the international community as a whole would not be a ected”); also Ragazzi, Concept 67 ; Fischer/Köck N. 258, according to which a jus cogens rule requires “moral unanimity” (moralische Einstimmigkeit) but can accommodate “one or the other outsider” (der eine oder andere Aussenseiter). Contra Shelton, AJIL 100 (2006) 300 (“[Article 53] precludes an individual State from vetoing the emergence of a peremptory norm”).

52Villiger, Customary International Law N. 49.

53Ibid. N. 52; on responsibility, see Scobbi, EJIL 13 (2002) 1201 .

54Roberts, AJIL 95 (2001) 784.

55Delbrück/Wolfrum III 711; Bleckmann, Völkerrecht N. 306; Rozakis, Concept 85.

56Statement by Yasseen in the ILC, YBILC 1963 I 73, para. 76.

57See on this para. Villiger, Customary International Law N. 292 , with further references; Kontou, passim; contra Rozakis, Concept 91.

58Villiger, Customary International Law N. 315.

59Or only by norms of the same character, N. 16.

60Rumpf, Festschrift Meissner 562.

Given the likely customary basis of peremptory norms (N. 9), any attempt to “photograph” them in a written instrument would overlook their dynamic nature.61 Whatever catalogue of such norms was established, discussions would inevitably arise as to other norms not mentioned therein. In any event, establishing a list of peremptory rules would have completely overtaxed both the ILC and the subsequent Vienna Conference.62

19In its Report of 1966 the ILC mentioned by way of illustration some examples of peremptory norms.63

The examples suggested were the unlawful use of force contrary to Article 2, para. 4 of the UN Charter, the performance of criminal acts under international law; and the commission of acts such as the trade in slaves, piracy, or genocide. Other ILC members added the examples of human rights, and the principle of the equality of States and of self-determination. It is tentatively argued elsewhere that pacta sunt servanda does not constitute jus cogens (Article 26, N. 6).

This commentary is not the place to discuss these and other examples of peremptory norms within the framework of the practice of States and international tribunals. Reference may be made, inter alia, to the lists of possible jus cogens rules compiled by Sztucki and Kadelbach64 and the study of Zemanek.65

3. Invalidity Rule (First Sentence)

20The first sentence of Article 53 provides the actual rule. In point of time it concerns, on the one hand, an existing peremptory rule, and, on the other, a treaty at the time of its conclusion (as distinguished from Article 64, q.v., which concerns the case of a treaty concluded before the peremptory norm emerged). The rule assumes a conflict between a treaty and a peremptory norm of general international law. There is a conflict if the treaty which is being concluded cannot—not even by employing all means of interpretation in Articles 31 and 32 (q.v.)—be performed in the future without breaching jus cogens. In such a case, the treaty will automatically be void, i.e., it will have no legal force. The treaty’s invalidity applies ab

61Villiger, Customary International Law N. 429, with reference to Baxter RC 129 (1970 I) 42, 96. See the Italian delegation in Vienna, OR 1969 Plenary 104, para. 38 (“rules of jus cogens . . . were in process of historical formation”). See the proposed UK amendment in Vienna, OR Documents 174, subpara. 462(ii)(d) (“peremptory norms . . . shall be defined from time to time in protocols to the Convention”).

62ILC Report 1966, YBILC 1966 II 248, para. 3

63YBILC 1966 II 248, para. 3; see the Barclona Traction Case, ICJ Reports 1970 32, para. 34; the Reservations to Genocide Advisory Opinion, ICJ Reports 1951 23; the Armed Activities on the Territory of the Congo (Democratic Republic of the Congo/Rwanda) Case, ICJ Reports 2006, para. 69 (“no such norm [of jus cogens] presently exists requiring a State to consent to the jurisdiction of the Court in order to settle a dispute relating to the Genocide Convention”).

64Sztucki, Jus cogens 77 , 119 ; Kadelbach, Zwingendes Völkerrecht 210 .

65Essays Tomuschat passim.

initio, as from its conclusion. Since no derogation to a peremptory norm is permitted (N. 10), States parties cannot inter se agree on the continuing validity of the treaty.66 In addition, the consequences listed in Article 71, para. 1 (q.v., N. 3–5) shall apply.

In the case of an invalid treaty according to Article 53, Article 44, para. 5 (q.v.) excludes the separation of its provisions.67 Moreover, Article 45 (q.v., N. 5) on the loss of a right to invoke a ground for invalidating a treaty does not apply to Article 53 since the latter implies automatic invalidity;

Impeachment of the treaty can be set in motion by any party to the treaty 21 invoking the ground of invalidity in Article 53. This party will notify the other party or parties to the treaty (Article 65, para. 1, N. 9–13). Should

an objection be raised, Article 65, para. 3 (q.v., N. 19–21) provides that the parties are under an obligation to seek a solution through the means indicated in Article 33 of the UN Charter. Where such a solution cannot be found, Article 66, para. (a) (q.v., N. 6–9) provides for compulsory dispute settlement (N. 4).

Thus, Article 53 excludes the unilateral determination by a State on its own of the alleged invalidity of the treaty. Third States are excluded from the procedures of Articles 65–68, although they may raise the matter as a breach of international law (and possibly of the UN Charter) before the UN Security Council or General Assembly. In addition, the UN can act on its own initiative.68 Given these complex procedures, it is doubtful whether one can ascribe to Article 53 a “punitive character”.69

C. RESERVATIONS

A number of States filed reservations under Article 53, and other States 22 objections thereto, in respect of the impeachment procedures (N. 21). They are dealt with in Article 66 (q.v., N. 11).

66ILC Report 1966, YBILC 1966 II 248, para. 4; Rozakis, Concept 35.

67Gaja, RC 172 (1981 III) 285; Rozakis, ibid. 122 ; Sztucki, Jus cogens 135 . Originally, Waldock Report II envisaged separability in Article 13, para. 3, YBILC 1963 II 52. The ILC agreed to leave this out; see the statement by Waldock in the ILC, YBILC 1963 I 291, para. 21.

68Frowein, EPIL 3 (1977) 67; Rozakis, ibid. 115 ; Sztucki, Jus cogens 123 , 129. In the ILC, Tsuruoka inquired whether a third State was allowed to intervene if the parties had concluded a secret treaty breaching jus cogens, YBILC 1963 I 67 f, para. 4.

69Fischer/Köck N. 258.

D. CONTEXT

1. Relationship to Other Provisions

23The relationship to various provisions has been mentioned above, e.g., Article 4 (N. 7), Article 30 (N. 6), Article 64 (N. 7), Articles 65–66 (N. 21) and Articles 69 and 71 para. 1 (N. 20). In addition, it may be noted that reservations are not permitted to treaties containing peremptory norms (Article 19, N. 13).70 Moreover, Article 52 (q.v.) most likely refers to a rule of jus cogens, though it is not in itself peremptory.

2.Matters Not Dealt With

24Article 53 concerns the invalidity of treaties only. It does not pronounce itself on the consequences of other norms, principles and situations conflicting with jus cogens (N. 10). Furthermore, Article 53 does not deal with regional jus cogens.71

3.Customary Basis of Article 53

25It could be argued that Article 53 was declaratory of customary law as from its inception. Thus, when the ILC commenced its discussions on Article 53, it did not intend to propose a completely new rule of treaty law.72 Furthermore, of the over 30 Governments which filed observations to the ILC on its Draft of 1963 (N. 2), only one called into question the existence of the concept of jus cogens.73 Finally, Article 53 was adopted by a relatively comfortable majority at the Vienna Conference (N. 4). There remain, however, the heated debates in Vienna. While these concerned mainly the lack of procedural safeguards surrounding Article 53, many States in their statements criticised the provision as a whole, thus undermining the opinio juris. It is, therefore, doubtful whether Article 53 could be

70See ILC Guideline 3.1.9 on Reservations Contrary to a Rule of jus cogens, YBILC 2007

II/2 99 (“[a] reservation cannot exclude or modify the legal e ect of a treaty in a manner contrary to a peremptory norm of general international law”); see also Articles 19–23—Subsequent Developments, N. 9.

71Bleckmann, Völkerrecht N. 300; critically Gaja, ibid. 284. An example would be the European Convention on Human Rights: in the Loizidou v. Turkey (Preliminary Objections) Case, the European Court of Human Rights regarded “the Convention as a constitutional instrument of European public order (ordre public)”, Series A no. 310, p. 27, para. 75.

72Waldock Report V, YBILC 1966 II 24 f, para. 6.

73Ibid., 23, para. 1 (Luxembourg); see also the ILC Report 1966, YBILC 1966 II 247, para. 1.

considered codificatory upon its adoption in 1969.74 On the other hand, the provision does not appear to have been called in question by States or tribunals since,75 and Article 53 may today be considered as an emerging rule of customary international law.76

appears exaggerated. In fact, the text is a masterpiece of precision and simplicity.81 Clearly, conflicts between treaties and jus cogens rules will

74Delbrück/Wolfrum III 712; Shelton, AJIL 100 (2006) 301 (with reference to the Vienna Conference.)

75See also the instances of court practice mentioned in N. 27.

76Suy, Article 53, N. 5 (“la communauté internationale accepte maintenant que la règle de la nullité d’un traité en raison d’un conflit avec une règle de droit impératif fait partie du droit positif”). For Kadelbach, Zwingendes Völkerrecht 46, Article 53 applies to non-Convention parties.

77Statement in Vienna by the Mexican delegation, OR 1968 CoW 294, para. 6. See also Rozakis, Concept 45 (“tautology”); the observation by the Dutch Government to the ILC in Waldock Report V, YBILC 1966 II 23, para. 2 (“pleonasm”).

78See Verhoeven, Essays Suy 196 (“[Article 53] simply states that there can be no jus cogens where States are not in agreement; this is far from circular”). Di erently Sinclair, Vienna Convention 220 on Article 53 (“however vague and shadowy it may be”).

79Tams, AVR 40 (2002) 341 (“besteht nach wie vor keine Einigkeit darüber, welche Konsequenzen die Einordnung eines Rechtssatzes als zwingende Völkerrechtsnorm hat”).

80Waldock Report II, YBILC 1963 II 53 para. 3.

81Statement in Vienna by the Indian delegation, OR 1968 CoW 307, para. 12.

remain exceptional.82 Even so, Article 53 has occasionally been invoked by tribunals.83 Given the cardinal importance of jus cogens for the international legal order, Article 53 amounts to one of the most important articles of the Convention.84 This is confirmed by the fact that the Convention devotes a total of four provisions to jus cogens (see also Articles 64, 66 para. [a] and 71).

82Statements by the delegations of Austria, OR 1968 CoW 303, para. 45; New Zealand, ibid. 312, para. 52; and then Ceylon, ibid. 319, para. 39. See also Zemanek, Essays Tomuschat 1117 (“States have not really be queueing up to have agreements voided”).

83See the International Criminal Tribunal for the Former Yugoslavia in the Case of Prosectuor v. Furundzija, ILR 121 (2002) 261; the US Court of Appeals in Siderman de Blake et al. v. Argentina et al., ILR 103 (1996) 470 f; and in Committee of US Citizens Living in Nicaragua v. Reagan, ILR 85 (1991) 260; the UK Court of Appeal in Al-Adsani v. Government of Kuwait et al., BYBIL 67 (1996) 540; also the Nuclear Weapons Advisory Opinion, ICJ Reports 1966 258, para. 83; the Gabcikovo-Nagymaros Project (Hungary/Slovakia) Case, ICJ Reports 1997 67, para. 112 (the Court noting that the parties had not argued that environmental rights fell under Article 64). Di erently Aust, Modern Treaty Law 320 (“no reported instances of Articles 53 and 64, as such, being seriously invoked”).

84Verhoeven, Essays Suy 195 (“one of the major achievements of the Vienna convention”).

Section . Termination and Suspension

of the Operation of Treaties

Article 54

Termination of or withdrawal from a treaty under its provisions or by consent of the parties

The termination of a treaty or the withdrawal of a party may take place:

(a)in conformity with the provisions of the treaty; or

(b)at any time by consent of all the parties after consultation with the other contracting States.

Article 54 Extinction d’un traité ou retrait en vertu des dispositions du traité ou par consentement des parties

L’extinction d’un traité ou le retrait d’une partie peuvent avoir lieu:

a)conformément aux dispositions du traité; ou,

b)à tout moment, par consentement de toutes les parties, après consultation des autres Etats contractants.

Artikel 54 Beendigung eines Vertrags oder Rücktritt vom Vertrag auf Grund seiner Bestimmungen oder durch Einvernehmen zwischen den Vertragsparteien

Die Beendigung eines Vertrags oder der Rücktritt einer Vertragspartei vom Vertrag können erfolgen

a)nach Massgabe der Vertragsbestimmungen oder

b)jederzeit durch Einvernehmen zwischen allen Vertragsparteien nach Konsultierung der anderen Vertragsstaaten.

ILC Draft 1966

Article 51—Termination of or withdrawal from a treaty by consent of the parties

A treaty may be terminated or a party may withdraw from a treaty:

(a)In conformity with a provision of the treaty allowing such termination or withdrawal; or

(b)At any time by consent of all the parties.

Materials:

WALDOCK Report II: Articles 15 and 18.

Minutes: YBILC 1963 I 93 , 236 , 292 f, 315, 317. ILC Draft 1964: Articles 38 and 40.

WALDOCK Report VI: Articles 38 and 40.

Minutes: YBILC 1966 I/1 41 , 48 , 96, 122, 125 f; YBILC 1966 I/2 224 f, 310, 332.

ILC Draft 1966: Article 51.

Minutes: OR 1968 CoW 334 , 476; OR 1969 Plenary 107 f.

Vienna Conference Vote: 105:0:0

Selected Literature:

M. Akehurst, Treaties, Termination, EPIL 4 (2000) 987 ; F. Capotorti, L’extinction et la suspension des traités, RC 134 (1971 III) 419 ; V. Chapaux, Article 54, in: Corten/ Klein (eds.) 1925 ; N. Kontou, The Termination and Revision of Treaties in the Light of New Customary International Law (1994); M.A. Martin López, La terminación y la supensión de los tratados internacionales a titulo de contramedida, Anuario de derecho internacional 15 (1999) 529 .

and often self-evident statements in two provisions of the subsequent Waldock Report II of 1963 which were criticised in the ILC in 1963 as containing “obvious truths” and being “somewhat lengthy”.5 However, at first the ILC lacked the courage substantially to shorten the text, only in 1966 was it decided to condense the two provisions and to join them.6 Article 51 of the ILC Draft 1966 contained the basis of today’s Article 54, though its title was imprecise in that it only referred to termination “by consent of the parties”.7 This oversight led to amendment proposals in Vienna; further proposals introduced as a condition under Article 54, para.

(b) the consultation of the “contracting States”.8 Article 54 was adopted by 105 votes to none.9

B. INTERPRETATION OF ARTICLE 54

1. Scope

3It follows from pacta sunt servanda, as in Article 26 (q.v.), that States cannot release themselves from treaty obligations at will.10 Section 3 of Part V of the Convention lists substantial and procedural rights for an orderly and lawful (Article 42, para. 2, N. 2) termination and suspension of the operation of treaties. The first provision, Article 54, stands very much at the centre of the Section, concerning as it does the general and obvious

5Articles 15 and 18, YBILC 1963 II 61 , 70 f. See, e.g., Article 15, para. 3: “In the case of a bilateral treaty which is expressed to be subject to denunciation or termination upon notice . . . the treaty shall continue in force until a notice of denunciation or termination has been given by one of the parties in conformity with the terms of the treaty”, ibid. 61. See furthermore the statements by Tunkin and Castren in the ILC, respectively, YBILC 1963 I 96, para. 35, and at 98, para. 66. Waldock explained in the ILC that “in a work of codification it was often necessary to state the obvious

explicitly”, ibid. 98, para., 66.

6See Articles 38 and 40, YBILC 1963 II 199 . The idea to join the provisions was raised for the first time by Briggs, YBILC 1966 I/1 43, para. 84; see also Waldock, ibid. 122, para. 5, and at 125, para. 57; YBILC 1966 I/2 224 f. The ILC had di culties adapting to a short text; Bartos complained that, if the ILC continued along these

lines “[it] would eventually leave nothing of the draft articles”. 7 ILC Report 1966, YBILC 1966 II 249.

8Proposals by Vietnam, on the one hand, and by the Netherlands and Hungary, on the other, OR Documents 175 f, paras. 471 . See the statement by the Vietnamese delega-

tion, OR 1969 Plenary 334, para. 2. 9 OR 1969 Plenary 108, para. 82.

10Akehurst, EPIL 4 (2000) 987; see also Haraszti, Some Fundamental Problems 280 .

préparatoires) that para. (a) concerns only express (written) provisions on the subject in the treaty.14 Whether or not there are such provisions in a treaty, is a matter of interpretation according to Articles 31 and 32 (q.v.).15 To the extent that no such provisions exist, para. (a) will not apply.

Such treaty provisions may limit the treaty’s duration by reference to a specific period, a date or an event. In addition, termination or denunciation may have either immediate e ect or occur after a particular period of time.16

11Statements by Vedross and Lachs in the ILC, YBILC 1963 I 94, para. 17, and at 95, para. 30.

12T he term “withdrawal” is usually applied for multilateral treaties. “Termination” also includes the denunciation of bilateral treaties, Delbrück/Wolfrum III 721 i.f.

13T he statement in Vienna by the Expert Consultant, Sir Humphrey Waldock, OR 1968 CoW 344, para. 61 (“[t]he parties were sovereign in the matter of separability and in that of suspension”); Waldock Report VI, YBILC 1966 II 30, para. 3; statement by Yasseen in the ILC, YBILC 1966 I/1 48, para. 68; Aust, Modern Treaty Law 288 f.

14E.g., Article 56 (q.v.) authorises a withdrawal where the parties “intended [this] possibility” or where such a right may be “implied by the nature of the treaty” (italics added ). See Yasseen of the Drafting Committee in Vienna, OR 1968 CoW 476, para. 4 (“a treaty may contain several provisions on its termination or on the withdrawal of a party”); Plender, BYBIL 57 (1986) 137 (“the tacit renewal . . . of treaties is not lightly to be established”). Note that subsequent or parallel agreements may be covered by Article 54, para. (b) (N. 6–8).

15ILC Report 1966, YBILC 1966 II 249, para. 1.

16Waldock Report II, YBILC 1963 II 61; see here also Article 55 (q.v.).

3. Consent of All Parties (Para. [b])

6Para. (b) envisages (in the alternative or cumulatively to para. [a], N. 5) termination or withdrawal by consent of all the parties after consultation with the other contracting States. Treaty parties are the masters of their own treaty and may at any time—contrary to any time-limit or other conditions stipulated by the treaty, and even if the treaty is silent—agree to its termination or in maiore minus the withdrawal of a particular State (N. 4).17

7Such termination or withdrawal requires first of all the consent of the parties. It follows from pacta sunt servanda (Article 26, q.v.) that on the contractual level18 a treaty’s termination or a party’s withdrawal in fact requires the conclusion of a new agreement, lying outside the original treaty.19 The crucial point is that consent of all the parties (in the case of a bilateral treaty: of the other party) will be required with regard to the termination of the treaty or to a State’s withdrawal. Thus, para. (b) steers clear of unilateral withdrawal; of any majority decision; and of termination inter se among some of the parties only (N. 10).20 As in Article 39 (q.v., N. 7), Article 54, para. (b) does not require an equal act, an acte contraire, for termination or withdrawal (N. 1 i.f.).21 The term “consent”, as opposed to “treaty”, indicates that there are di erent forms of termination or withdrawal which the parties are free to choose,22 e.g.:

–a subsequent written agreement, e.g., in a new treaty or even in communications between the parties, which will be considered together with the treaty itself according to Article 31, subpara. 2(a) (q.v., N. 18);

–an oral agreement, e.g., between Ministers or between a Foreign Minister and an ambassador acting on instructions (Article 7, q.v.);

17Waldock Report II, ibid. 64, para. 2. The ILC struggled with various time-limits as to how soon a treaty could be terminated after it was concluded; see, e.g., the proposal by the US Government, Waldock Report VI, YBILC 1966 II 29. See also Article 56, N. 7.

18In the ILC Waldock pointed out that Article 54, para. (b) only covered “all the grounds of termination coming within the law of treaties . . . There could be other cases where treaties were in e ect brought to an end but they did not come within the scope of the draft now under consideration”, YBILC 1966 I/2 225, para. 94.

19ILC Report 1963, YBILC 1963 II 202, para. 1; statement by the Dutch delegation in Vienna, OR 1968 CoW 335, para. 5.

20Both of which may, of course, be envisaged by the treaty under Article 54, para. (a) (N. 5).

21Statement by de Luna in the ILC, YBILC 1966 I/1 49, para. 72; Frankowska, Polish YBIL 7 (1975) 304.

22Sinclair, Vienna Convention 183; see on the following also the ILC Report 1966, YBILC 1966 II 249, para. 3; Waldock Report VI, ibid. 30, para. 2; Waldock Report II, YBILC 1963 II 70, para. 1.

N. 22) envisaged by Fitzmaurice and in the early stages also by Waldock (N. 2). The result is “a refreshingly simple text”.35 Article 54, emphasising the importance of the common will of the treaty parties, provides an important gateway into Section 3 on the termination and suspension of treaties in that it works in particular against unilateral assertions of a right to denounce the treaty.36 Still, Article 54 has to be read together with all other provisions of Section 3. Para. (a) of Article 54 reminds us of one lesson to be drawn from these provisions, namely the usefulness of including in the treaty clauses on its termination and denunciation.

33See the legal opinion of the Swiss Government, SJIR 36 (1980) 166; the statements by Gros and Yasseen in the ILC, YBILC 1963 I 96, para. 41, and 108, para. 20, respectively.

34Plender, BYBIL 57 (1986) 136. Article 54, para. (a) was invoked in the Sedco Inc. v. National Iranian Oil Company and the Islamic Republic of Iran Case before the IranUnited States Claims Tribunal by Judge Brower in his sep. op., ILR 84 (1987) 531, and by Judge Mosk in his concurring opinion, ibid. 663.

35K. Widdows, The Unilateral Denunciation of Treaties Containing no Denunciation Clause, BYBIL 53 (1982) 84.

36Waldock Report II, YBILC 1963 II 70, para. 1.

Article 55

Reduction of the parties to a multilateral treaty below the number necessary for its entry into force

Unless the treaty otherwise provides, a multilateral treaty does not terminate by reason only of the fact that the number of the parties falls below the number necessary for its entry into force.

Article 55 Nombre des Parties à un traité multilatéral tombant au-dessous du nombre nécessaire pour son entrée en vigueur

À moins que le traité n’en dispose autrement, un traité multilatéral ne prend pas fin pour le seul motif que le nombre des Parties tombe au-dessous du nombre nécessaire pour son entrée en vigueur.

Artikel 55 Abnahme der Zahl der Vertragsparteien eines mehrseitigen Vertrags auf weniger als die für sein Inkrafttreten erforderliche Zahl

Sofern der Vertrag nichts anderes vorsieht, erlischt ein mehrseitiger Vertrag nicht schon deshalb, weil die Zahl der Vertragsparteien unter die für sein Inkrafttreten erforderliche Zahl sinkt.

ILC Draft 1966

Article 52—Reduction of the parties to a multilateral treaty below the number necessary for its entry into force

Unless the treaty otherwise provides, a multilateral treaty does not terminate by reason only of the fact that the number of the parties falls below the number specified in the treaty as necessary for its entry into force.

Materials:

WALDOCK Report II: Article 15, para. 4.

Minutes: YBILC 1963 I 93 , 236 , 292 f, 315, 317. ILC Draft 1963: Article 38, subpara. 3(b).

WALDOCK REPORT V: Article 38.

Minutes: YBILC 1966 I/1 41 , 96, 122 f; YBILC 1966 I/2 311, 332.

ILC Draft 1966: Article 52.

Minutes: OR 1968 CoW 336, 476 f; OR 1969 Plenary 108.

Vienna Conference Vote: 105:0:0

Selected Literature (in addition to the literature mentioned in Article 54, q.v.):

V. Chapaux, Article 55, in: Corten/Klein (eds.) 1945 .

the principle, and comments concerned mainly drafting issues.4 The rule was expressly supported by three of the altogether five States commenting on the ILC Draft 1963.5 In 1966 the ILC reorganised the provisions of Section 3 of Part V, while unanimously adopting Article 52 (the present Article 55).6 At the Vienna Conference in 1968 the provision attracted few observations, the only amendment being of a stylistic nature.7 In 1969 no comments were made, and Article 55 was adopted by 105 votes to none.8

4Members attached particular importance to the principle: see the statements by Waldock, YBILC 1963 I 98, para. 67, and 236, para. 44; Yasseen, ibid. 95, para. 20;

Lachs, ibid. paras. 30 f; and Bartos, ibid. paras. 32 .

5 I.e., Finland, Portugal and Sweden, Waldock Report VI, YBILC 1966 II 25. 6 YBILC 1966 I/2 332; see also YBILC 1966 I/1 122, para. 5.

7An amendment successfully proposed by the United Kingdom suggested deleting the words “specified in the treaty” in Article 52 of the ILC Draft 1966. Of the few States tak-

ing the floor, Romania expressly supported the provision, OR 1968 CoW 336, para. 15. 8 OR 1969 Plenary 108, para. 82.

9Simma, Reziprozitätselement 55 f. Di erently Delbrück/Wolfrum III 731 (three States parties).

10See the ILC Report 1966, YBILC 1966 II 250, para. 2; Waldock Report II, YBILC 1963 II 62 f, para. 7.

11Aust, Modern Treaty Law 289; see also the reasons given by Bartos in the ILC, YBILC 1963 I 95 f, para. 32, as to concessions which a State may have made to entice other States to become a party.

Article 56

Denunciation of or withdrawal from a treaty containing no provision regarding termination, denunciation or withdrawal

1.A treaty which contains no provision regarding its termination and which does not provide for denunciation or withdrawal is not subject to denunciation or withdrawal unless:

(a)it is established that the parties intended to admit the possibility of denunciation or withdrawal; or

(b)a right of denunciation or withdrawal may be implied by the nature of the treaty.

2.A party shall give not less than twelve months’ notice of its intention to denounce or withdraw from a treaty under paragraph 1.

Article 56 Dénonciation ou retrait dans le cas d’un traité ne contenant pas de dispositions relatives à l’extinction, à la dénonciation ou au retrait

1.Un traité qui ne contient pas de dispositions relatives à son extinction et ne prévoit pas qu’on puisse le dénoncer ou s’en retirer ne peut faire l’objet d’une dénonciation ou d’un retrait, à moins:

a)qu’il ne soit établi qu’il entrait dans l’intention des parties d’admettre la possibilité d’une dénonciation ou d’un retrait; ou

b)que le droit de dénonciation ou de retrait ne puisse être déduit de la nature du traité.

2.Une partie doit notifier au moins douze mois à l’avance son intention de dénoncer un traité ou de s’en retirer conformément aux dispositions du paragraphe 1.

Artikel 56 Kündigung eines Vertrags oder Rücktritt von einem Vertrag, der keine Bestimmung über Beendigung, Kündigung oder Rücktritt enthält

1.Ein Vertrag, der keine Bestimmung über seine Beendigung enthält und eine Kündigung oder einen Rücktritt nicht vorsieht, unterliegt weder der Kündigung noch dem Rücktritt, sofern

a)nicht feststeht, dass die Vertragsparteien die Möglichkeit einer Kündigung oder eines Rücktritts zuzulassen beabsichtigten, oder

b)ein Kündigungsoder Rücktrittsrecht sich nicht aus der Natur des Vertrags herleiten lässt.

2.Eine Vertragspartei hat ihre Absicht, nach Absatz 1 einen Vertrag zu kündigen oder von einem Vertrag zurückzutreten, mindestens zwölf Monate im voraus zu notifizieren.

ILC Draft 1966

Article 53—Denunciation of a treaty containing no provision regarding termination

1.A treaty which contains no provision regarding its termination and which does not provide for denunciation or withdrawal is not subject to denunciation or withdrawal unless it is established that the parties intended to admit the possibility of denunciation or withdrawal.

2.A part shall give not less than twelve months’ notice of its intention to denounce or withdraw from a treaty under paragraph 1 of this article.

Materials:

WALDOCK Report II: Articles 16 f.

Minutes: YBILC 1963 I 98 , 239 , 293 f, 315, 318.

ILC Draft 1963: Article 39.

WALDOCK Report V: Article 39.

Minutes: YBILC 1966 I/1 43 , 122 f; YBILC 1966 I/2 310, 332.

ILC Draft 1966: Article 53.

Minutes: OR 1968 CoW 336 , 477; OR 1969 Plenary 108 .

Vienna Conference Vote: 95:0:6

Selected Literature: (in addition to the literature mentioned in Article 54, q.v.):

D. Bardonnet, La dénonciation par le Gouvernement Sénégalais de la Convention sur la mer terriotriale et la zone contiguë et de la Convention sur la pêche et la conservation des ressources biologiques de la haute mer en date à Genève du 29 avril 1958, AFDI 18 (1972) 123 ; Th. Christakis, Article 56, in: Corten/Klein (eds.) 1951 ; R.P. Cima, Unilateral Termination of the 1954 Mutual Defence Treaty Between the United States and the Republic of China Pursuant to the President’s Foreign Relations Power, Vanderbilt JTL 12 (1979) 133 ; K. Widdows, The Unilateral Denunciation of Treaties Containing No Denunciation Clause, BYBIL 53 (1982) 83 .

A. BACKGROUND

1. Introduction

1 There has long been a discussion in international law as to whether in respect of a treaty containing no withdrawal or denunciation clause: (i) the treaty parties had deliberately excluded unilateral termination of the treaty; or, conversely, (ii) whether they had overlooked the possibility and were not opposed to it; or even (iii) whether they had tacitly approved withdrawal.1 An early recognition of the rule of non-withdrawal can be found in the 1871 London Declaration which, following Russia’s attempt to withdraw from the 1856 Treaty of Paris, stated that “it is an essential principle of the law of nations that no power can liberate itself from the

engagements of a treaty . . . unless with the consent of the contracting parties”.2 Conversely, the 1928 Havana Convention on Treaties provided in Article 17 that “in the absence of . . . a stipulation, a treaty may be denounced by any contracting State, which shall notify the others of this

1See McNair, Law of Treaties 493, 501 , 504; Giraud, Annuaire IDI 49 (1961 I) 73 ; for an overview of the positions in literature and State practice, see Feist, Kündigung

199, 202 .

2British and Foreign State Papers 61 at 1198, cited in the Harvard Draft, AJIL 29 (1935) Supplement 1177.

favourable comments from 13 Governments.11 The final ILC Draft 1966 mentioned solely the intentions of the parties as the criterion to establish the possibility of a right of denunciation.12

3This sole criterion of the intentions of the parties resulted in the tabling of five amendments at the 1968/1969 Vienna Conference. South American Governments in particular criticised the notion of “perpetual treaties” aimed at extending the possibility of denunciation.13 Surprisingly, while only the UK amendment was adopted (aimed at inserting as a further criterion, as in 1963, the “character” of the treaty),14 in fact the new subpara. 1(b) introduced at the Conference goes back to the South American/Spanish amendments which relied on the “nature” of the treaty.15 Article 56 was adopted in 1969 by 95 votes to none, with six abstentions—the abstaining States expressing worries as to the impact of subpara. 1(b) on the stability of treaty regimes in international law.16

B. INTERPRETATION OF ARTICLE 56

1. General Rule (Opening Sentence of Para. 1)

4Article 56 proceeds from the assumption that treaty parties wishing to enable one party’s unilateral termination of a treaty will have stated as much in the treaty, and that the treaty’s silence in fact implies that they wished to exclude such a possibility.17 Accordingly, Article 56 expounds the general rule that a treaty which contains no provision regarding its termination and which does not provide for denunciation or withdrawal is not subject to denunciation or withdrawal.18 (Note that according to

Article 54, para. [b] [q.v., N. 6], unilateral termination is always possible with the consent of all other treaty parties.)

“Denunciation” appears to refer to a bilateral treaty, “withdrawal” to a multilateral treaty.19 Nevertheless, it is not clear why other provisions of the Convention—e.g.,

11Waldock Report VI, YBILC 1966 II 25 .

12Adopted unanimously by 18 votes to none, YBILC 1966 I/1 122, para. 14.

13See, inter alia, the statements by the delegations of Cuba, OR 1968 CoW 336f; Peru, ibid. 337, para. 28; and Spain, ibid. 338, para. 38.

14OR 1968 CoW 343, para. 54; OR Documents 177, subpara. 487(d).

15OR Documents 177, para. 478; di erently Sinclair, Vienna Convention 187.

16OR 1969 Plenary 110, para. 8; see, e.g., the observations of the delegations of Italy, OR 1969 Plenary, 108 ; and Finland, OR 1968 CoW 477, para. 14.

17See the ILC Report 1966, YBILC 1966 II 250, paras. 1 f.

18T his general rule reflects practice and doctrine, Feist, Kündigung 207.

19Neuhold/Hummer/Schreuer, Österreichisches Handbuch N. 391. Article 56 does not distinguish between biand multilateral treaties, Waldock Report II, YBILC 1963 II 67, para. 14.

insu cient; the other treaty parties must have consented thereupon.25 For instance, upon conclusion of a treaty, or even thereafter, a party may state that it reserves the right to denounce the treaty, and the other States can expressly or implicitly accept.26 Of course, interpretation may also reveal the treaty parties’ intention not to permit unilateral termination of the treaty.

Thus, in the Gabcikovo-Nagymaros Project (Hungary/Slovakia) Case, the Court found no such intention in the treaty at issue.27 On the whole, Widdows has regarded subpara. 1(a) as irrelevant.28 Still, given the countless treaties concluded by States and their subsequent practice thereupon, it appears di cult to rule out a priori and de plano such intention of all treaty parties in respect of all past and future treaties. The value of subpara. 1(a) also lies therein that it shows States concluding a treaty how to deal with the eventualities of denunciation and withdrawal.

Subpara. 1(a) and Article 54, para. (b) (q.v., N. 6–8), while conceptually di erent, may converge. The former provides for the possibility of a tacit agreement among the treaty parties granting one treaty party the right to give notice.29 On the other hand, Article 54, para. (b) envisages the tacit agreement of all States parties to terminate the entire treaty. In maiore minus this includes the possibility of all States agreeing to one State unilaterally terminating the treaty.

8Subpara. 1(b) provides the second exception, namely that a right of denunciation or withdrawal may be implied by the nature of the treaty. The criterion of a treaty’s nature, going back to Fitzmaurice Report II (N. 2)30 and re-introduced at the Vienna Conference (N. 3), has been much criticised.31 A treaty’s nature includes its object and purpose (as in Article 31, para. 1, N. 17). While the nature of every treaty must be interpreted individually, a generalisation seems feasible in that treaties

25Waldock Report VI, YBILC 1966 II 27, para. 2; the ILC Report 1963, YBILC 1963 II 202, para. 5.

26Example given by Ago in the ILC, YBILC 1966 I/1 47, para. 58; see also Delbrück/ Wolfrum III 727.

27“Nor is there any indication that the parties intended to admit the possibility of denunciation or withdrawal . . . Consequently, the parties not having agreed otherwise, the Treaty could be terminated only on the limited grounds enumerated in the Vienna Convention”, ICJ Reports 1994 62 f, para. 100.

28See Widdows BYBIL 53 (1982) 113 (who apparently will not search for the “intention” in subsequent practice): “in the usual circumstances, no common intention can be found on the part of the signatories: they either do not wish to discuss the question, do not wish to provide a termination clause, or are optimistically relying on the law to provide a residual rule either in favour of a right of denunciation or against such a right, depending on which textbook had been perused”.

29Statement by Yasseen in the ILC, YBILC 1966 I/1 47, para. 59 (contra, ibid. 43, para. 5).

30See the words “ex naturae” (N. 2 at n. 6), YBILC 1957 II 22.

31Sinclair, Vienna Convention 187 (“not easy to apply”); Neuhold/Hummer/Schreuer, Österreichisches Handbuch N. 393 (“kein glücklich gewählter Ausdruck”). Widdows, BYBIL 53 (1982) 113, regards subpara. 1(b) as a “total failure”, albeit without appearing to analyse the criterion of the treaty’s “nature.”

with an intrinsically temporary character appear of a “nature” to permit unilateral termination.32

will be of relevance in the following situation: interpretation according to subpara. 1(a) may disclose that no denunciation or withdrawal was intended, whereas an interpretation of the nature of the treaty according to subpara. 1(b) may reveal the contrary. Given the independence of subpara. (b), the latter will prevail, and unilateral termination will be possible (unless, of

32Sinclair ibid.; Feist, Kündigung 207 (who, at ibid., 208 excludes unilateral termination if the treaty ensures interests of the State community); Capotorti, RC 134 (1971 III) 539; Elias, Law of Treaties 107. See also McNair, Law of Treaties 505, for whom

denunciation is possible if a treaty includes a “bilateral bargain”.

33 T here was disagreement in the ILC in 1963 as to the various examples, YBILC 1963 I 99 . See the list in Christakis, Article 59, N. 77–98.

34See Article 17, subpara. 3(a) of Waldock Report II, YBILC 1963 II 64 and 68, paras. 15 ; Aust, Modern Treaty Law 290 f. Whether treaties on judicial settlement allow for unilateral denunication in the absence of any express provision, was left open in the Fisheries Jurisdiction (UK v. Iceland) Case, ICJ Reports 1973 15 , paras. 25, 29.

35See Article 17, para. 4 of Waldock Report II ibid.; the 1966 ILC Report, YBILC 1966 II 250, para. 2; Aust, ibid.

36Aust, ibid. See the denunciation by the Democratic Popular Republic of Korea of the UN Covenant on Civil and Political Rights; J.D. Hommeaux, Jurisprudence du Comité des droits de l’homme des Nations Unies (novembre 1991–novembre 1998), AFDI 44 (1998) 615 .

37Verdross/Simma N. 807; see also Aust, Modern Treaty Law 290; Sinclair, Vienna Convention 187; Bardonnet, AFDI 18 (1972) 123 .

course, there is a clause in the treaty excluding denunciation or withdrawal altogether, N. 4).38

3. Procedure (Para. 2)

11If the exceptions in subparas. 1(a) or (b) authorise denunciation of or withdrawal from a treaty, the treaty party concerned is called upon to follow the procedure set out in para. 2. Thus, the party shall give notice of its intention to denounce or withdraw from a treaty. All parties of the treaty must be notified, though no particular form is prescribed. If the notification is to serve a useful purpose, the other parties are entitled to obtain adequate information as to the State’s intention. There is no requirement for the other States to consent to the notification. When a State does so— expressly or implicitly—it can be argued that an agreement has been reached according to Article 54, para. (b) (q.v., N. 6–8).39

12The period of notice shall be not less than twelve months (i.e., before the date when the State intends unilaterally to terminate the treaty.) This period, which reflects State practice,40 is su ciently long to give adequate protection to the interests of the other parties and to enable further negotiations.41

In the Interpretation of the Agreement of 25 March 1951 between the WHO and Egypt Advisory Opinion, the Court referred to the period in para. 2 as a useful indication for States when considering the “periods of time . . . involved in the observance of the duties to consult and negotiate”.42

C. CONTEXT

1. Relationship to Other Provisions

13Article 44, para. 1 (q.v., N. 8) provides that a party’s right under Article 56 may be exercised only with respect to the entire treaty, unless the treaty otherwise provides or the parties otherwise agree.

38Capotorti, RC 134 (1971 III) 539; Jennings/Watts N. 648 n. 2; contra Delbrück/ Wolfrum III 727.

39Delbrück/Wolfrum III 729; Neuhold/Hummer/Schreuer, Österreichisches Handbuch N. 392.

40See the Swiss Federal Council’s Message to Parliament on the Convention, BBl 1989 II 784; Capotorti, RC 134 (1971 III) 485.

41Statement in Vienna the UK delegation (Vallat), OR 1968 CoW 339, para. 2; the ILC Report 1966, YBILC II 251, para. 6. The (unsatisfacatory) alternative would have been to require “reasonable” notice, Waldock Report II, YBILC 1963 II 68, para. 19.

42ICJ Reports 1980 96, para. 49; see reference to various opinions below at N. 16.

Subpara. 1(b), introduced by various Governments at the Vienna Conference, was disputed among some States; this led to six abstentions in the final vote, though Article 56 as a whole was adopted with a sound majority (N. 3). Authors who have criticised Article 56 do not appear conclusively to call in question its declaratory nature.47 On the whole, the provision seems to have generated a new rule of customary law.48

43Delbrück/Wolfrum III 730; Aust, Modern Treaty Law 287, who refers to Article 317, para. 2 of the 1982 UN Convention on the Law of the Sea; see also Article 17 of the 1928 Havanna Convention on Treaties, cited in the Harvard Draft, AJIL 29 (1935) Supplement 1174.

44See also Waldock Report II, YBILC 1963 II 67, para. 10; the statement in Vienna by the Spanish delegation, OR 1968 CoW 338, para. 39.

45Kearney/Dalton, AJIL 64 (1970) 538 f; Delbrück/Wolfrum III 728; see the statements in Vienna by the Chairman of the Draft Committee, Yasseen, OR 1969 Plenary 132, para. 3: “it was quite clear that paragraph 1 [of Article 65] applied to all claims brought under the preceding articles in Part V”; and by the Australian delegation, ibid. 110, para. 3. However, the time-limit in Article 65, para. 2 appears superseded by para. 2 of Article 56, Delbrück/Wolfrum III 728 at n. 84.

46Statement by Rosenne in the ILC, YBILC 1963 I 103, para. 37 (“the Commission was engaged in framing a rule de lege ferenda”).

47Widdows, BYBIL 53 (1982) 113, by pointing out that the provision is “not based on current State practice”, appears to refer to the position confronting the ILC in 1963 (N. 2). Capotorti, RC 134 (1971 III) 540, regards para. 2 as not reflecting customary law, though at ibid. 485, he seems to argue that State practice frequently employs the clause therein; see also Akehurst, EPIL 4 (2000) 988.

48In the Interpretation of the Agreement of 25 March 1951 between the WHO and Egypt Advisory Opinion (N. 12), Judges Gros, Mosler, Oda, el-Erian and Sette-Camara referred in their respective opinions to Article 56, ICJ Reports 1980 475 f, 478 f, 480, 513, 560, 570, and 573, though, interestingly, without reference to Articles 65–68 (N.

D. WITHDRAWAL FROM THE CONVENTION

17May a State unilaterally withdraw from the Convention? The latter contains no provisions regarding its termination and withdrawal. In such a situation, the Convention is governed by its own provisions, including Article 56 (Issues of Customary International Law, N. 24–27). The issue then arises whether the exceptions in subparas. 1(a) or (b) (N. 6–10) are met in the case of the Convention. However, it appears unnecessary to find a reply since the Convention is generally declaratory of customary international law and its provisions continue to bind all States even after a party’s withdrawal from the Convention (Article 43, q.v.; Issues of Customary International Law, N. 52).

E. APPRECIATION

18Even if some authors have directed trenchant criticism at Article 56,49 it has not been shown that the set of rules in particular in subparas. 1(a) and (b) has since proved di cult (or impossible) for States to employ in their practice. Clearly, this important topic—the unilateral termination of a treaty which is silent on the matter—required normative regulation in the Convention.50 The solution, widely supported by States in Vienna, provides for a sound balance between the general rule and the exceptions, between stability and orderly change. The provision operates within pacta sunt servanda and thus strengthens it (N. 6).51

15). In the Fisheries Jurisdiction (United Kingdom v. Iceland) Case, Pleadings I 254 f, the UK Government considered Article 56 as being declaratory of customary international law (cited by Widdows, BYBIL 53 [1982] 98). It may be argued that in the GabcikovoNagymaros Project (Hungary/Slovakia) Case, ICJ Reports 1997 62, para. 100, the Court proceeded implicitly from Article 56 of the Convention which it therefore regarded as applicable qua customary law (“[n]or is there any indication that the parties intended to admit the possibility of denunciation or withdrawal”).

49Widdows, ibid. (“the Article is in its entirety so problematical that it provides no clear residual rule and thus leaves States in the same confusion as they have been in for centuries past“); see also the comments on this view in N. 7–9; Capotorti, RC 134 (1971) 539 (“bien loin d’être précis”).

50See the statement in Vienna by the Venezuelan delegation, OR 1968 CoW 340, para. 15 (“one of the most complex problems in contemporary international law”).

51WAldock in the ILC, YBILC 1963 I 100, para. 5 (“[a] carefully regulated implied right of denunciation governed by proper procedural requirements make for stability and for respect for treaties and international law”).

Article 57

Suspension of the operation of a treaty under its provisions or by consent of the parties

The operation of a treaty in regard to all the parties or to a particular party may be suspended:

(a)in conformity with the provisions of the treaty; or

(b)at any time by consent of all the parties after consultation with the other contracting States.

Article 57 Suspension de l’application d’un traité en vertu de ses dispositions ou par consentement des parties

L’application d’un traité au regard de toutes les parties ou d’une partie déterminée peut être suspendue:

a)conformément aux dispositions du traité; ou,

b)à tout moment, par consentement de toutes les parties, après consultation des autres Etats contractants.

Artikel 57 Suspendierung eines Vertrags auf Grund seiner Bestimmungen oder durch Einvernehmen zwischen den Vertragsparteien

Ein Vertrag kann gegenüber allen oder einzelnen Vertragsparteien suspendiert werden:

a)nach Massgabe der Vertragsbestimmungen oder

b)jederzeit durch Einvernehmen zwischen allen Vertragsparteien nach Konsultierung der anderen Vertragsstaaten.

ILC Draft 1966

Article 54—Suspension of the operation of a treaty by consent of the parties

The operation of a treaty in regard to all the parties or to a particular party may be suspended:

(a)in conformity with a provision of the treaty allowing such suspension;

(b)at any time by consent of all the parties after consultation with the other contracting States.

Materials:

WALDOCK Report II: Article 18, para. 5.

Minutes: YBILC 1963 I 107 , 241 , 315 f, 318. ILC Draft 1963: Article 40, para. 3.

WALDOCK Report V: Article 40, para. 3.

Minutes: YBILC 1966 I/1 48 , 125 ; YBILC 1966 I/2 129 , 224 , 311, 332.

ILC Draft 1966: Article 54.

Minutes: OR 1968 CoW 343 f, 477; OR 1969 Plenary 108, 110.

Vienna Conference Vote: 101:0:0

Selected Literature:

F. Capotorti, L’extinction et la suspension des traités, RC 134 (1971 III) 419 ; R. Huesa Vinaixa, Article 57, in: Corten/Klein (eds.) 2015 .

agreement but contained in para. 5 a provision on the present topic.2 At first the ILC had little to say on the matter,3 the ILC Draft 1963 merely pointing out that the principles of today’s Article 54 (q.v.) also governed Article 57.4 Only one Government filed an observation on this provision, finding it a “useful innovation”.5 In 1966 there was a growing unease in the ILC at combining the two provisions, and a further confusion arose

1 AJIL 29 (1035) Supplement 657 ; the Report by Rosenne, Annuaire IDI 52 (1967 I) 5 .

2 YBILC 1963 II 70.

3 E.g., the statement by Castren in the ILC, YBILC 1963 I 108, para. 15. 4 Article 40, para. 3 of the Draft ILC 1963, YBILC 1963 II 203, para. 5. 5 I.e., Sweden, Waldock Report VI, YBILC 1966 II 29.

in the context of the present Article 58 (q.v., N. 1).6 The first independent treatment of the matter was contained in the ILC Draft 1966.7 The little discussion which the provision attracted arose at the 1968/1969 Vienna Conference where the title and the content of the provision were brought into alignment with today’s Article 54.8 Article 57 was adopted by 101 votes to none.9

B. INTERPRETATION OF ARTICLE 57

3All the parties, some of the parties, or a particular party have the possibility of suspending the operation of a treaty. The latter becomes inoperative for the parties for a particular time though the treaty regime itself is not a ected (Article 72, N. 3). Suspension may concern the entire treaty or only parts of it (Article 44, q.v.).10 T he parties may resort to suspension, for instance, if they temporarily encounter di culties concerning the performance of their obligations under the treaty. In such a situation, the possibility of suspension—as an alternative in particular to its termination—appears useful since it does not a ect the treaty regime itself (Article 72, q.v.).11

4Article 57 is intentionally modelled on Article 54, and the same principles apply (in maiore minus). Thus, the suspension may occur in conformity with the provisions of the treaty, or at any time by consent of all the parties after consultation with the other contracting States. Accordingly, the interpretation of these conditions follows, mutatis mutandis, those of

Article 54 (q.v., N. 3-8).

6See the statements by Ago, YBILC 1966 I/1 49, para. 84 (“odd”, “clumsy text”); by Yasseen, de Luna, Tunkin, Pessou, Castren, and Rosenne, ibid. 126 ; and by

Jiménez de Aréchaga, YBILC 1966 I/2 129 f, paras. 7 . 7 Article 56, YBILC 1966 II 251 f.

8See, e.g., the statement in Vienna by the Chairman of the Drafting Committee, Yasseen, OR 1969 Plenary 108, para. 75; and the vote on the the second part of Article 57, subpara. (b), ibid. 110, para. 11. On the Conference proceedings generally, see

Elias, Modern Law of Treaties 108. 9 OR 1969 Plenary 110, para. 11.

10Statement in Vienna by the Expert Consultant, Sir Humphrey Waldock, OR 1968 CoW 344, para. 61; Capotorti, RC 134 (1971 III) 502.

11Waldock Report II, YBILC 1963 II 71, para. 9; the ILC Report 1966, YBILC 1966 II 252, para. 1; the statements in the ILC by Waldock, YBILC 1963 I 108, para. 9; and Jiménez de Aréchaga, YBILC 1966 I/2 130, para. 7.

Article 58

Suspension of the operation of a multilateral treaty by agreement between certain of the parties only

1.Two or more parties to a multilateral treaty may conclude an agreement to suspend the operation of provisions of the treaty, temporarily and as between themselves alone, if:

(a)the possibility of such a suspension is provided for by the treaty; or

(b)the suspension in question is not prohibited by the treaty and:

(i) does not a ect the enjoyment by the other parties of their rights under the treaty or the performance of their obligations;

(ii) is not incompatible with the object and purpose of the treaty.

2.Unless in a case falling under paragraph 1(a) the treaty otherwise provides, the parties in question shall notify the other parties of their intention to conclude the agreement and of those provisions of the treaty the operation of which they intend to suspend.

Article 58 Suspension de l’application d’un traité multilatéral par accord entre certaines parties seuelement

1.Deux ou plusieurs parties à un traité multilatéral peuvent conclure un accord ayant pour objet de suspendre, temporairement et entre elles seulement, l’application de dispositions du traité:

a)si la possibilité d’une telle modification est prévue par le traité; ou

b)si la suspension en question n’est pas interdite par le traité, à condition qu’elle:

i) ne porte atteinte ni à la jouissance par les autres parties des droits qu’elles tiennent du traité ni à l’exécution de leurs obligations; et

ii) ne soit pas incompatible avec l’objet et le but du traité.

2.À moins que, dans le cas prévu à l’alinéa a) du paragraphe 1, le traité n’en dispose autrement, les parties en question doivent notifier aux autres parties leur intention de conclure l’accord et les dispositions du traité dont elles ont l’intention de suspendre l’application.

Art. 58 Suspendierung eines mehrseitigen Vertrags auf Grund einer Übereinkunft zwischen einzelnen Vertragsparteien

1.Zwei oder mehr Vertragsparteien eines mehrseitigen Vertrags können eine Übereinkunft zur zeitweiligen, nur zwischen ihnen wirksamen Suspendierung einzelner Vertragsbestimmungen schliessen,

a)wenn eine solche Suspendierungsmöglichkeit im Vertrag vorgesehen ist oder

b)wenn die Suspendierung durch den Vertrag nicht verboten ist, vorausgesetzt,

i) dass sie die anderen Vertragsparteien im Genuss ihrer Rechte auf Grund des Vertrags oder in der Erfüllung ihrer Pflichten nicht beeinträchtigt und

ii) dass sie mit Ziel und Zweck des Vertrags nicht unvereinbar ist.

2.Sofern der Vertrag in einem Fall des Absatzes 1 lit. a nichts anderes vorsieht, haben diese Vertragsparteien den anderen Vertragsparteien ihre Absicht, die Übereinkunft zu schliessen, sowie diejenigen Vertragsbestimmungen zu notifizieren, die sie suspendieren wollen.

ILC Draft 1966

Article 55—Temporary suspension of the operation of a multilateral treaty by consent between certain of the parties only

When a multilateral treaty contains no provision regarding the suspension of its operation, two or more parties may conclude an agreement to suspend the operation of provisions of the treaty temporarily and as between themselves alone if such suspension:

(a)does not a ect the enjoyment by the other parties of their rights under the treaty or the performance of their obligations; and

(b)is not incompatible with the e ective execution as between the parties as a whole of the object and purpose of the treaty.

Materials:

Minutes: YBILC 1966 I/1 48 , 125 f; YBILC 1966 I/2 129 , 224, 226 f, 311 f, 332.

ILC Draft 1966: Article 55.

Minutes: OR 1968 CoW 347 , 472; OR 1969 CoW 224, 309 f; OR 1969 Plenary 111.

Vienna Conference Vote: 102:0:0

Selected Literature:

F. Capotorti, L’extinction et la suspension des traités, RC 134 (1971 III) 419 ; M.P. Lanfranchi, Article 58, in: Corten/Klein (eds.) 2067 .

of the ILC Draft 19665—constituting a separate article and reflecting certain conditions of modification inter se, though today’s para. 2 was still missing.6 At the Vienna Conference in 1968 a six-State-amendment was adopted,7 which in 1969 led to a provision now mirroring to a large extent Article 41.8 The content of the rule itself was only briefly discussed.9 Article 58 was adopted by 102 votes to none.10

B. INTERPRETATION OF ARTICLE 58

2Article 58 concerns the suspension of the operation of a multilateral treaty by agreement between certain of the parties only. If a treaty is suspended inter se, it becomes inoperative for some parties for a particular period of time, though the treaty régime itself is not a ected (Article 72, N. 3). Suspension thus di ers substantially from the termination of a treaty as in Article 54 (q.v.).11

Article 58 may be seen as a useful temporary expedient for certain States finding themselves in di culties in operating the treaty. Ex hypothesi, suspension inter se does not a ect the other parties (Article 34, q.v.).12 By putting an end to suspension inter se, the parties concerned will bring themselves back into line with the other States.13

3In regulating suspension inter se, the ILC intentionally resorted to the conditions of modification inter se of multilateral treaties expounded in Article 41 (q.v.). An analogy was seen between the two provisions, since parties to a multilateral treaty wishing to modify it among themselves may, as a first step, wish to suspend its operation inter se.14

5 YBILC 1966 II 252.

6“Its omission . . . is not to be understood as implying that the parties in question may not have a certain general obligation to inform the other parties of their suspension inter se of the operation of the treaty”, ILC Report 1966, YBILC 1966 II 252, para. 2. The ILC only noticed that para. 2 was missing when discussing its final Report in

10OR 1969 Plenary 111, para. 13.

11Statement in the ILC by its Chairman, Bartos, YBILC 1966 I/2 132, para. 34.

12T he other parties have an interest in the normal continuance of the treaty; see the statement by Jiménez de Aréchaga in the ILC, YBILC 1966 I/2 130, para. 11.

13Statement by Waldock in the ILC, ibid. 132, para. 29.

14Statements in the ILC by Ago, ibid. para. 39; and Waldock, ibid. 129, para. 4.

suspension in question is not prohibited by the treaty. Moreover, it is stipulated in subparas. (b)(i) and (ii) that the suspension inter se does not a ect the enjoyment by the other parties of their rights under the treaty or the performance of their obligations and, cumulatively, that it is not incompatible with the object and purpose of the treaty (see on these conditions Article 41, N. 6–9).19

15But see Capotorti, RC 134 (1971 III) 510 (“le contenu de l’article 58 reflète strictement celui de l’article 41”). Note also the di erences between Articles 41 and 58 in both the French and German versions.

16See the formulation in para. 2 (“those provisions of the treaty”, N. 7); the ex cathedra interpretation at the Vienna Conference by the Chairman of the Drafting Committee, Yasseen, OR 1969 CoW 310, para. 32. In Vienna, an attempt to exclude so-called integral multilateral treaties from the application of Article 58 proved unsuccessful; see the statement by the Australian delegation, OR 1968 CoW 348, paras. 9 .

17See also Article 57 (q.v., N. 3), envisaging the suspension of a treaty “in regard . . . to a particular party”. Capotorti, RC 134 (1971 III) 469, refers here to Article 71, subpara. 1(a) (q.v., N. 4).

18Statement by Waldock in the ILC, YBILC 1966 I/1 126, para. 84.

19In Vienna, the Senegalese delegation mentioned a treaty for the improvement and economic development of a river basin as an example of suspension going against a treaty’s object and purpose; an agreement inter se to suspend such a treaty’s operation between some of the parties would undermine the operation of the treaty as a whole, OR 1968 CoW 350, para. 29.

As the Commentary to the ILC Guidelines of 2007 points out in the context of reservations, reference to the object and purpose in subpara. 1(b)(ii) does not appear to compel respect for the treaty as such (since it is precisely the purpose of this provision to determine the conditions of suspension), but to preserve what is essential in the views of the contracting parties.20

7Para. 2 lists further procedural conditions as to notification of suspension inter se (except if under subpara. 1[a] the treaty otherwise provides), namely that the parties in question shall notify the other parties of their intention to conclude the agreement and of those provisions of the treaty the operation of which they intend to suspend (see on these conditions Article 41, N. 10–13).21 T he modalities of notifi cation are explained in Article 78 (q.v.).

C. CONTEXT

1. Relationship to Other Provisions

8The consequences of the suspension of the operation of a treaty are dealt with in Article 72 (q.v.). Article 58 does not exclude the application of Article 60 regarding the breach of treaties (q.v.).22 It is also possible that eventually all parties agree to suspend the multilateral treaty, in which case

Article 57 (q.v.) will apply.

9If another treaty party objects to suspension inter se, the procedures in

Articles 65–68 (q.v.) will apply.23

2. Customary Basis of Article 58

10As in Article 41 (q.v., N. 18) and in Article 57 (q.v., N. 2), the various details listed in subparas. 1(a) and (b) and para. 2 appeared innovatory when the ILC took up its study on the matter. They have since not been called in question by States, for which reason the provision as a whole may be considered as having become declaratory of customary international law.

20Commentary to ILC Guideline 3.1.5 on the Incompatibility of a Reservation with the Object and Purpose of the Treaty, YBILC 2007 II/2 67, n. 2; also Articles 19–23— Subsequent Developments N. 3 .

21Fischer/Köck N. 262. In Vienna, the Peruvian delegation regarded notification as a matter of international courtesy, OR 1968 CoW 347, para. 3. For Zemanek of the Austrian delegation, notification lay in the interests of the security of treaties, ibid. para. 5.

22Statement by Waldock in the ILC, YBILC 1966 I/2 133, paras. 53 f.

23See the statement in Vienna by the Mexican delegation, OR 1968 CoW 348, para. 13.

Article 59

Termination or suspension of the operation of a treaty implied by conclusion of a later treaty

1.A treaty shall be considered as terminated if all the parties to it conclude a later treaty relating to the same subject-matter and:

(a)it appears from the later treaty or is otherwise established that the parties intended that the matter should be governed by that treaty; or

(b)the provisions of the later treaty are so far incompatible with those of the earlier one that the two treaties are not capable of being applied at the same time.

2.The earlier treaty shall be considered as only suspended in operation if it appears from the later treaty or is otherwise established that such was the intention of the parties.

Article 59 Extinction d’un traité ou suspension de son application implicites du fait de la conclusion d’un traité postérieur

1.Un traité est considéré comme ayant pris fin lorsque toutes les parties à ce traité concluent ultérieurement un traité portant sur la même matière et:

a)s’il ressort du traité postérieur ou s’il est par ailleurs établi que selon l’intention des parties la matière doit être régie par ce traité; ou

b)si les dispositions du traité postérieur sont incompatibles avec celles du traité antérieur à tel point qu’il est impossible d’appliquer les deux traités en même temps.

2.Le traité antérieur est considéré comme étant seulement suspendu s’il ressort du traité postérieur ou s’il est par ailleurs établi que telle était l’intention des parties.

Artikel 59 Beendigung oder Suspendierung eines Vertrags durch Abschluss eines späteren Vertrags

1.Ein Vertrag gilt als beendet, wenn alle Vertragsparteien später einen sich auf denselben Gegenstand beziehenden Vertrag schliessen und

a)aus dem späteren Vertrag hervorgeht oder anderweitig feststeht, dass die Vertragsparteien beabsichtigten, den Gegenstand durch den späteren Vertrag zu regeln, oder

b)die Bestimmungen des späteren Vertrags mit denen des früheren Vertrags in solchem Masse unvereinbar sind, dass die beiden Verträge eine gleichzeitige Anwendung nicht zulassen.

2.Der frühere Vertrag gilt als nur suspendiert, wenn eine solche Absicht der Vertragsparteien aus dem späteren Vertrag hervorgeht oder anderweitig feststeht.

ILC Draft 1966

Article 56—Termination or suspension of the operation of a treaty implied from entering into a subsequent treaty

1.A treaty shall be considered as terminated if all the parties to it conclude a further treaty relating to the same subject-matter and:

(a)It appears from the treaty or is otherwise established that the parties intended that the matter should thenceforth be governed by the later treaty, or

(b)The provisions of the later treaty are so far incompatible with those of the earlier one that the two treaties are not capable of being applied at the same time.

2.The earlier treaty shall be considered as only suspended in operation if it appears from the treaty or is otherwise established that such was the intention of the parties when concluding the later treaty.

Materials:

WALDOCK Report II: Article 19.

Minutes: YBILC 1963 I 114 , 196 , 243 f, 316, 318.

ILC Draft 1963: Article 41.

WALDOCK Report V: Article 41.

Minutes: YBILC 1966 I/1 54 , 127; YBILC I/2 312, 332.

ILC Draft 1966: Article 56.

Minutes: OR 1968 CoW 350 , 477 f; OR 1969 Plenary 108, 111.

Vienna Conference Vote: 104:0:0

Selected Literature (in addition to the literature mentioned in Article 30, q.v.):

F. Dubuisson, Article 59, in: Corten/Klein (eds.) 2091 .

parties, to the extent that the provisions of the later treaty are inconsistent with the provisions of the earlier treaty”.1 This influenced Article 59 less than the separate opinion of Judge Anzilotti in the Electricity Company of Sofia and Bulgaria Case in which he commented on a conflict between unilateral declarations under the Optional Clause and a treaty:

“[t]here was no express abrogation. But it is generally agreed that, beside express abrogation, there is also tacit abrogation resulting from the fact that the new provisions

1AJIL 29 (1935) Supplement 1009. The Draft envisaged the separability of superseded treaty provisions, ibid. 1010. See also the statement by Briggs in the ILC, YBILC 1963 I 118, para. 42.

are incompatible with the previous provisions, or that the whole matter which formed the subject of these latter is henceforward governed by the new provisions.”2

2. History

2The topic was introduced in Waldock Report II in 1963.3 The ILC had some di culties with the provision, both as regards its place in the draft and its relation with today’s Article 30 (q.v., N. 3).4 Governments, on the other hand, were generally in agreement with the provision.5 Article 56 of the ILC Draft 1966 largely reflected the present Article 59.6 At the 1968 Vienna Conference, the few amendments submitted were mainly of a technical nature. In 1969 in Vienna, there was no further discussion on the matter.7 Article 59 was adopted by 104 votes to none.8

At the Vienna Conference, a Canadian amendment proposed inserting in the opening sentence the words “in whole or in part”, and to add in subpara. 1(b) the terms “so far incompatible with those of the earlier one that not all of the provisions of the two treaties are capable of being applied at the same time”.9 T he delegation wished that “that portion of the earlier treaty which was not incompatible with the later treaty to remain in force”.10 However, the Conference did not accept the amendment, as it would have had the undesired e ect that “termination should be implied whenever the subsequent treaty had an impact on some of the provisions of the earlier treaty”.11 Already Waldock Report V had unsuccessfully attempted to include a similar formulation.12

2PCIJ (1939) Series A/B no. 77, 92. See the ILC Report 1966, YBILC 1966 II 253, para. 2; the criticism thereof by Rosenne in the ILC, YBILC 1963 I 115, para. 9; the diss. op. of Judge Basdevant in the Minquiers and Ecrehos (United Kingdom/France) Case, ICJ Reports 1952 66 , 70 f; the practice mentioned by Aust, Modern Treaty

Law 218 , and Plender, BYBIL 57 (1986) 154. 3 YBILC 1963 II 71.

4 Castren in the ILC, YBILC 1966 I/1 56, para. 65. See the debate in 1963, YBILC 1963 I 115 ; the criticism directed against the proposal by Rosenne, ibid. 115 f.

5 Waldock Report V, YBILC 1966 II 31 (with the exception of the Israeli Government). 6 Ibid. 252.

7OR Documents 180, para. 514 (amendments by Austria, Canada, the then Byelorussian SSR, Romania and China); see also OR 1968 CoW 350 , 477 f; the criticism voiced by the delegation of Israel (Rosenne), ibid. 351, para. 51 (“completely redundant and

merely repetitious of other provisions of the draft”); OR 1969 Plenary 111, para. 13. 8 OR 1969 Plenary 111, para. 13.

9 OR Documents 180, subpara. 514(b).

10OR 1968 CoW 351, para. 46.

11See the statement in Vienna by the Expert Consultant, Sir Humphrey Waldock, OR 1968 CoW 352, para. 55. (In fact, Sir Humphrey appeared to have misunderstood the amendment: its purpose was precisely not to have the entire early treaty terminated.) Contra Sadat-Akhavi, Methods of Resolving Conflicts Between Treaties (2003) 51 f.

12See the revised text in YBILC 1966 I/1 54, para. 40 (“[i]f the provisions of the later treaty relate only to a part of the earlier treaty and the two treaties are otherwise capable

by the travaux préparatoires of Article 59—that the term “treaty” refers to the entire treaty, the later one substituting en bloc and, hence, abrogating the earlier one.17 Article 59 does not, therefore, apply where only some of the provisions of the earlier and the later treaty are incompatible with each other. In this case, the entire earlier treaty will remain in force.

The considerations concerning the Canadian amendment in Vienna (N. 2) give an indication, e.g., as to the application of Article 59 in the relation between the 1982 UN Law of the Sea Convention and the 1958 Geneva Conventions on the law of the sea. Article 311, para. 1 of the former provides that it “shall prevail, as between States Parties, over the Geneva Conventions”. It is unlikely that Article 59 comes into play here, since it would have to be established: (i) that all the States parties to any of the 1958 Conventions have also become parties to the 1982 Convention;

of being applied at the same time, that part alone shall be considered as terminated or suspended in operation”); previously the ILC Draft 1963, YBILC 1963 II 203.

13See also Bleckmann, Völkerrecht N. 380b (“wenn der spätere Vertrag . . . einen anderen ‘Geist’ hat”).

14See Capotorti, RC 134 (1971 III) 500 (“phénomène de révision conventionnelle”).

15See the ILC Report 1966, YBILC 1966 II 252, para. 1.

16Aust, Modern Treaty Law 292, sees a presumption here that the earlier treaty will be abrogated.

17Delbrück/Wolfrum III 724, N. 4.

and (ii) that the Law of the Sea Convention is “so far incompatible” with all the provisions of the Geneva Conventions “that the two treaties are not capable of being applied at the same time”, as required by subpara. 1(b) (N. 11)18

7The termination of the earlier treaty occurs informally and is implied once the later treaty has been concluded (there is no express termination or modification of the earlier treaty). It is here where Article 59 can be distinguished from Article 30 (q.v.).

If the treaty is not terminated because one or more of the conditions in Article 59 have not been met (e.g., because not all the parties of the earlier treaty are parties to the later treaty [N. 4] or because only some of the provisions of the earlier treaty are a ected [N. 6]), then the two treaties continue to exist alongside each other—and Article 30 will determine the priority among them.19 Hence, Article 30 is subsidiary to Article 59.20

8In addition to the above (N. 3–7), the conditions of subpara. 1(a) or of subpara. 1(b) must alternatively be met (N. 9–11) in order to bring about the termination of the earlier treaty. In either case, there is a strong overlap with Article 54 (q.v.).

2. Subjective Test: Intentions of the Parties (Subpara. 1[a])

9Subpara. 1(a) envisages two situations (N: 9–10), each requiring an interpretation of the later treaty. The first situation concerns the text itself of the later treaty. Thus, it may appear from the later treaty that the matter should be governed by that treaty rather than the earlier one which, therefore, the parties intended to abrogate.

10Second, it may be otherwise established that the parties intended, when concluding the later treaty, implicitly to terminate the earlier treaty.21 Indications herefor may be found in a wide variety of means other than the treaty text,22 inter alia, in the travaux préparatoires of the later treaty, for instance, in statements at the preparatory conference or in the circumstances of its conclusion.23

18Delbrück/Wolfrum, ibid., speak here somewhat cryptically of an “hierarchical order”.

19See the ILC Report 1966, YBILC 1966 II 253, para. 4.

20Wilting, Vertragskonkurrenz 80; Aust, Modern Treaty Law 228 (“residual rules in Article 30”).

21Capotorti, RC 134 (1971 III) 499 (“d’une façon quelconque”).

22T he Vienna Conference did not accept an amendment by the then Byelorussian SSR wishing to limit para. 1 to the “treaty or . . . some other instrument relating thereto”, OR Documents 180, para. 514 (c); see the statement by the Byelorussian delegation, OR 1968 CoW 351, para. 48.

23Waldock Report V, YBILC 1966 II 33; see also the statements in the ILC by Waldock, YBILC 1966 I/1 54, para. 40; Yasseen, YBILC 1963 I 117, para. 37; and Briggs, ibid. 118, para. 41; also Verdross/Simma 514.

This will be the case, if all the conditions of para. 1 (N. 4–11) have been met whereas (in contrast to para. 1) it appears from the later treaty or is otherwise established that such—i.e., the earlier treaty’s suspension rather than its abrogation—was the intention of the parties. The parties therefore have a choice of letting the earlier treaty become inoperative for a particular period of time as an alternative to its termination.27 They may wish to do so, for instance, if the later treaty is only concluded for a fixed duration.28

The ILC considered that “in most cases it is probable that [the parties’] intention would have been to cancel rather than suspend the earlier treaty”29—a statement which, given the advantages of the flexibility of suspension, appears too categorical.

24Capotorti, RC 134 (1971 III) 499 at n. 26. He appears too emphatic when he states, ibid., that subpara. 1(b) envisages termination “indépendamment de l’intention des parties au traité”, since the parties to the two treaties may well have been aware of (and therefore have intended) the mutual incompatibility of the treaties. See also Plender, BYBIL 57 (1986) 154, for whom “only in the most exceptional cases” will it be necessary to rely on subpara. 1(b); Wilting, Vertragskonkurrenz 81.

25See the ILC Report 1966, YBILC 1966 252 f, para. 1; Aust, Modern Treaty Law 292.

26T he Portuguese Government’s observation to the ILC considered that para. 2 was already included in para. 1; see Waldock Report V, YBILC 1966 II 31.

27Capotorti, RC 134 (1971 III) 501 (“il reste à établir si la non-application du traité antérieur est considérée dans l’intention des parties comme une situation temporaire”).

28Ibid.

29ILC Report 1966, YBILC 1966 II 253, para. 3.

Based on an observation by Sir Humphrey Waldock at the Vienna Conference in connexion with Article 57 (q.v.),30 Capotorti considers that Article 59, para. 2 permits partial suspension of the earlier treaty (as opposed to its partial abrogation which is not possible, N. 6).31

C. CONTEXT

1. Relationship to Other Provisions

13The relationship between Article 59 and other provisions has been assessed above, in particular Articles 30 (N. 7), 39–41 and 54 (N. 3). The consequences of termination and suspension are mentioned in Articles 70 and

72(q.v.).

2.Matters Not Dealt With

14It has been argued that Article 59 does not apply if only some of the provisions of the earlier and the later treaty are incompatible with each other (N. 6)32 or, where not all the parties to the earlier treaty are parties to the later treaty (N. 4).33

3.Customary Basis of Article 59

15There is virtually no practice on Article 59.34 Given the support it obtained in the ILC and in Vienna (N. 2), it can be assumed that the provision reflects a customary rule.

D. APPRECIATION

16Plender has criticised Article 59 to the extent that, if the conclusion of the later treaty is not clear evidence of the parties’ consent to modify the earlier treaty, then “the problem is one of interpretation” (and if it is clear evidence, the rule in Article 59 is “otiose”).35 Even so, Article 59 remains useful in that it provides important elements guiding the interpretation

30OR 1968 CoW 344, para. 61.

31Capotorti, RC 134 (1971 III) 502.

32Aust, Modern Treaty Law 293, considers that in this situation Article 59 applies mutatis

mutandis.

33Contra, Sadat-Akhavi, Methods of Resolving Conflicts Between Treaties (2003) 51 f.

34See the statement by Rosenne in the ILC, YBILC 1963 I 115, para. 10.

35BYBIL 57 (1986) 153.

of the two treaties, inter alia, the extent to which they are compatible with each other (N. 12). On the whole, the conditions of Article 59 are strict: all the parties must wish to substitute the entire earlier treaty with the later treaty. There is also a psychological barrier: treaty parties may wish to steer clear from the notion of informal abrogation of the earlier treaty. In practice, therefore, the application of Article 59 will most likely remain exceptional.

Article 60

Termination or suspension of the operation of a treaty as a consequence of its breach

1.A material breach of a bilateral treaty by one of the parties entitles the other to invoke the breach as a ground for terminating the treaty or suspending its operation in whole or in part.

2.A material breach of a multilateral treaty by one of the parties entitles:

(a)the other parties by unanimous agreement to suspend the operation of the treaty in whole or in part or to terminate it either:

(i) in the relations between themselves and the defaulting State, or

(ii) as between all the parties;

(b)a party specially a ected by the breach to invoke it as a ground for suspending the operation of the treaty in whole or in part in the relations between itself and the defaulting State;

(c)any party other than the defaulting State to invoke the breach as a ground for suspending the operation of the treaty in whole or in part with respect to itself if the treaty is of such a character that a material breach of its provisions by one party radically changes the position of every party with respect to the further performance of its obligations under the treaty.

3.A material breach of a treaty, for the purposes of this article, consists in:

(a)a repudiation of the treaty not sanctioned by the present Convention; or

(b)the violation of a provision essential to the accomplishment of the object or purpose of the treaty.

4.The foregoing paragraphs are without prejudice to any provision in the treaty applicable in the event of a breach.

5.Paragraphs 1 to 3 do not apply to provisions relating to the protection of the human person contained in treaties of a humanitarian character, in particular to provisions prohibiting any form of reprisals against persons protected by such treaties.

Article 60 Extinction d’un traité ou suspension de son application comme conséquence de sa violation

1.Une violation substantielle d’un traité bilatéral par l’une des parties autorise l’autre partie à invoquer la violation comme motif pour mettre fin au traité ou suspendre son application en totalité ou en partie.

2.Une violation substantielle d’un traité multilatéral par l’une des parties autorise:

a)les autres parties, agissant par accord unanime, à suspendre l’application du traité en totalité ou en partie ou à mettre fin à celui-ci:

i) soit dans les relations entre elles-mêmes et l’Etat auteur de la violation,

ii) soit entre toutes les parties;

b)une partie spécialement atteinte par la violation à invoquer celle-ci comme motif de suspension de l’application du traité en totalité ou en partie dans les relations entre elle-même et l’Etat auteur de la violation;

c)toute partie autre que l’Etat auteur de la violation à invoquer la violation comme motif pour suspendre l’application du traité en totalité ou en partie en ce qui la concerne si ce traité est d’une nature telle qu’une violation substantielle de ses dispositions par une partie modifie radicalement la situation de chacune des parties quant à l’exécution ultérieure de ses obligations en vertu du traité.

3.Aux fins du présent article, une violation substantielle d’un traité est constituée par:

a)un rejet du traité non autorisé par la présente Convention; ou

b)la violation d’une disposition essentielle pour la réalisation de l’objet ou du but du traité.

4.Les paragraphes qui précèdent ne portent atteinte à aucune disposition du traité applicable en cas de violation.

5.Les paragraphes 1 à 3 ne s’appliquent pas aux dispositions relatives à la protection de la personne humaine contenues dans des traités de caractère humanitaire, notamment aux dispositions excluant toute forme de représailles

àl’égard des personnes protégées par lesdits traités.

Artikel 60 Beendigung oder Suspendierung eines Vertrags infolge Vertragsverletzung

1.Eine erhebliche Verletzung eines zweiseitigen Vertrags durch eine Vertragspartei berechtigt die andere Vertragspartei, die Vertragsverletzung als Grund für die Beendigung des Vertrags oder für seine gänzliche oder teilweise Suspendierung geltend zu machen.

2.Eine erhebliche Verletzung eines mehrseitigen Vertrags durch eine Vertragspartei

a)berechtigt die anderen Vertragsparteien, einvernehmlich den Vertrag ganz oder teilweise zu suspendieren oder ihn zu beenden

i) entweder im Verhältnis zwischen ihnen und dem vertragsbrüchigen Staat

ii) oder zwischen allen Vertragsparteien;

b)berechtigt eine durch die Vertragsverletzung besonders betro ene Vertragspartei, die Verletzung als Grund für die gänzliche oder teilweise Suspendierung des Vertrags im Verhältnis zwischen ihr und dem vertragsbrüchigen Staat geltend zu machen;

c)berechtigt jede Vertragspartei ausser dem vertragsbrüchigen Staat, die Vertragsverletzung als Grund für die gänzliche oder teilweise Suspendierung des Vertrags in bezug auf sich selbst geltend zu machen, wenn der Vertrag so bescha en ist, dass eine erhebliche Verletzung seiner Bestimmungen durch eine Vertragspartei die Lage jeder Vertragspartei hinsichtlich der weiteren Erfüllung ihrer Vertragsverpflichtungen grundlegend ändert.

3.Eine erhebliche Verletzung im Sinne dieses Artikels liegt

a)in einer nach diesem Übereinkommen nicht zulässigen Ablehnung des Vertrags oder

b)in der Verletzung einer für die Erreichung des Vertragsziels oder des Vertragszwecks wesentlichen Bestimmung.

4.Die Absätze 1 bis 3 lassen die Vertragsbestimmungen unberührt, die bei einer Verletzung des Vertrags anwendbar sind.

5.Die Absätze 1 bis 3 finden keine Anwendung auf Bestimmungen über den Schutz der menschlichen Person in Verträgen humanitärer Art, insbesondere auf Bestimmungen zum Verbot von Repressalien jeder Art gegen die durch derartige Verträge geschützten Personen.

ILC Draft 1966

Article 57—Termination or suspension of the operation of a treaty as a consequence of its breach

1.A material breach of a bilateral treaty by one of the parties entitles the other to invoke the breach as a ground for terminating the treaty or suspending its operation in whole or in part.

2.A material breach of a multilateral treaty by one of the parties entitles:

(a)the other parties by unanimous agreement to suspend the operation of the treaty in whole or in part or to terminate it either:

(i) in the relations between themselves and the defaulting State, or

(ii) as between all the parties;

(b)a party specially a ected by the breach to invoke it as a ground for suspending the operation of the treaty in whole or in part in the relations between itself and the defaulting State;

(c)any party to suspend the operation of the treaty with respect to itself if the treaty is of such a character that a material breach of its provisions by one party radically changes the position of every party with respect to the further performance of its obligations under the treaty.

3.A material breach of a treaty, for the purposes of the present article, consists in:

(a)a repudiation of the treaty not sanctioned by the present articles; or

(b)the violation of a provision essential to the accomplishment of the object or purpose of the treaty.

4.The foregoing paragraphs are without prejudice to any provision in the treaty applicable in the event of a breach.

Materials:

WALDOCK Report II: Article 20.

Minutes: YBILC 1963 I 120 , 245, 294 f.

ILC Draft 1963: Article 42.

WALDOCK Report V: Article 42. Minutes: YBILC 1966 I/1 59 , 127 .

ILC Draft 1966: Article 57.

Minutes: OR 1968 CoW 352 , 478; OR 1969 Plenary 111 , 167 f.

Vienna Conference Vote: 88:0:7

Selected Literature:

A-H

R.B. Bilder, Breach of Treaty and Response Thereto, PASIL 61 (1967) 193 ; H.W. Briggs, Procedures for Establishing the Invalidity or Termination of Treaties under the International Law Commission’s ILC Draft Articles on the Law of Treaties, AJIL 61 (1967) 976 ; Id., Unilateral Denunciation of Treaties: The Vienna Convention and the International Court of Justice, AJIL 68 (1974) 53 ; F. Capotorti, L’extinction et la suspension des traités, RC 134 (1971 III) 419 ; A.E. David, The Strategy of Treaty Termination (1975); Ch. Feist, Kündigung, Rücktritt und Suspendierung von multilateralen Verträgen (2001); M. Fitzmaurice, Material Breach of Treaty: Some Legal Issues, Austrian RIEL 6 (2001) 3 ; M.M. Gomaa, Suspension or Termination of Treaties on Grounds of Breach (1996); D.N. Hutchinson, Solidarity and Breaches of Multilateral Treaties, BYBIL 58 (1988) 151 .

K-P

M. Kawano, Legal Consequences of the Breach of Multilateral Treaties, in: M. Iwasaki (ed.), Varieties of Regional Integration (1995) 29 ; F.L. Kirgis, Some Lingering Questions About Article 60 of the Vienna Convention on the Law of Treaties, Cornell ILJ 22 (1989) 549 ; C. Laly-Chevalier, La violation du traité (2005); M.A. Martin López, La terminación de los tratados internacionales a titulo de contramedida, Anuario de derecho internacional 15 (1999) 529 ; St.C. Neff, Boycott and the Law of Nations: Economic Warfare and Modern International Law in Historical Perspective, BYBIL 59 (1988) 135 ; R. Nisot, L’exception “non adimpleti contractus” en droit international, RGDIP 74 (1970) 668 ; R. Pisillo Mazzeschi, Risoluzione e sospensione dei trattati per inadempimento (1984).

R-Y

Sh. Rosenne, Breach of Treaty (1985); Id., Terminaison des traités collectifs, Annuaire IDI 52 (1967-I) 25 ; E. Schwelb, Termination or Suspension of the Operation of a Treaty as a Consequence of Its Breach, IJIL 7 (1967) 309 ; B. Simma, Reflections on Article 60 of the Vienna Convention on the Law of Treaties and Its Background in General International Law, ÖZöR 20 (1970) 5 ; Id., Termination and Suspension of Treaties. Two Recent Austrian Cases, GYBIL 21 (1978) 74 ; Id., Zum Rücktrittsrecht wegen Vertragsverletzung nach der Wiener Konvention von 1969, in: H. Kipp/F. Mayer/A Steinkamm (eds.), Um Recht und Freiheit. Festschrift für F.A. von der Heydte (1977) 615 ; B. Simma/Ch.J. Tams, Article 60, in: Corten/Klein (eds.) 2131 ; B.P. Sinha, Unilateral Denunciation of Treaty Because of Prior Violations of Obligations by Other Party (1966); Q. Wright, The Termination and Suspension of Treaties, AJIL 61 (1967) 1000 ; A. Yahi, La violation d’un traité: L’articulation du droit des traités et du droit de la responsabilité internationale, RBDI 26 (1993) 437 .

authors to formulate definite rules, though to others, for instance Rousseau, the situation was “passablement obscure”.1 It was generally admitted that,

1Droit international public I 213 f; see also O’Connell, International Law I 267. D.D. Field, Outlines of an International Code, 2nd ed. (1876), stated in N. 202 (5) that

if a party violated its treaty obligations, this did not eo ipso bring about an end of the operation of the treaty, though a disturbance in the equilibrium of obligations would permit some kind of reaction (exceptio non adimpleti contractus; inadimplenti non est adimplendum).2 T his view was argued by Belgium in the 1937 Diversion of Water from the Meuse Case and upheld in opinions of Judges Anzilotti and Hudson, though the Permanent Court did not pronounce itself on the matter.3 It was also agreed that the consequences of a breach of obligation did not occur ipso facto and had to be invoked within a reasonable period of time.4 The 1935 Harvard Draft provided in Article 27, para. (a) a link between the violation of a treaty and an independent procedure.5 Other issues were in dispute to a greater degree, for instance, the type and extent of the breach of treaty required to bring about such consequences.6 In the 1925 Tacna-Arica Arbitration, the arbitrator required for the termination of the relevant agreement the establishment of “such serious conditions as the consequence of administrative wrongs as would operate to frustrate the purpose of the agreement”.7 Other authorities dismissed as “quasi impraticable” the doctrine of material breach and a distinction between essential and non-essential provisions.8

2. History

2Article 60 traces its roots to the Fitzmaurice Report II of 1957 which proceeded from a narrow definition of a fundamental breach of treaty and confined the consequences of termination or suspension mainly to bilateral

“an obligation created by treaty is extinguished . . . (5) by breach of its conditions by the nation entitled to performance”, cited in Harvard Draft, AJIL 29 (1935) Supplement 1208. Bluntschli, Le droit international codifié, 3rd ed. (1881), envisaged in Article 455 that when one of the contracting parties failed to carry out its undertakings or violated the treaty, the injured party was entitled to consider itself released from its obligations. For the basis of this commentary, see Villiger, Customary International Law N. 519–550.

2Simma, ÖZöR 20 (1970) 19 f; Gomaa, Suspension 95. Rosenne pointed out in the ILC that suspension had equally not been used in a retaliatory manner, YBILC 1966

I/1 162, para. 97.

3PCIJ Series A/B (1937) no. 70, 8, 38, 50, 77. Judge Anzilotti regarded the principle as “so just, so equitable, so universally recognized”, and as a general principle of law,

ibid. 50.

4 McNair, Law of Treaties 571; Harvard Draft, AJIL 29 (1935) Supplement 1093. 5 AJIL 29 (1935) Supplement 1077 .

6 See Neuhold, AVR 15 (1971/72) 48.

7AJIL 19 (1925) 415; also McNair, Law of Treaties 571; Guggenheim, Traité I 226 f; Jennings, RC 121 (1967 II) 566 f.

8Rousseau, Droit international public I 214; A. Verdross, Völkerrecht, 5th ed. (1964), 178; and his 1st ed (1937),. 92, with references to Grotius and de Vattel.

the provision, and stressed the importance of the issue. On the other hand, delegations discussed questions of separability, the directness of e ects of a breach of treaty, and the definition of material breach. All amendments were rejected with few dissenting votes, but with comparatively many abstentions.16 In 1969 the Conference adopted, inter alia, a Swiss amendment introducing a new para. 5 on humanitarian conventions (N. 23–24).17 Article 60 was adopted by 88 votes to none, with seven abstentions.18

9Articles 17–20, in particular Article 19, subparas. 1(i) and 2[ii]–[iv], and para. 2, YBILC 1957 II 29 , 52 ; see also Articles 17A–20 and 34–39 of the Fitzmaurice Report IV of 1959, YBlLC 1959 II 45 . The ILC did not discuss these articles. On the history, see Neff, BYBIL 59 (1988) 185 ; Rosenne, Breach of Treaty 8 ; Feist,

Kündigung 146 , 156 f.

10YBILC 1963 II 72 .

11T he debate is reproduced ibid. 75, para. 11.

12See the debate at YBILC 1963 I 120 , and 245 .

13YBILC 1966 I/I 59 , 127 ; and I/2 312 f. See ibid. 129, para. 30; Article 57 is reproduced in YBILC 1966 II 253 .

14According to Rosenne, ibid. I/I 60, paras. 24 f, the concept of States a ected in their interests was “ill-defined in international law”. Verdross saw in the doctrine of material breach a “first attempt” at definition, ibid. 61, para. 38. Sir Humphrey suggested, ibid. 65, para. 13, that subpara. 2(b) was more limited “than generally understood by lawyers”.

15Reproduced in OR Documents 181 f.

16See OR 1968 CoW 359 paras. 79 .

17OR 1969 Plenary 111 f, paras. 14 ; and the debate, ibid.

18Ibid. 116, para. 81.

B. INTERPRETATION OF ARTICLE 60

1. Scope

5Article 60 sets out the substantive conditions under which a treaty may be terminated or its operation suspended in consequence of a breach. The provision aims at balancing competing interests and thereby to disturb as little as possible the international legal order.19 On the one hand, upon a breach of treaty the injured State acting in good faith should be a orded certain rights vis-à-vis the defaulting State. In particular, the injured party should not be called upon to fulfil its obligations under a treaty when the other party fails to fulfil those obligations which it undertook under the same treaty (principle of reciprocity). 20 On the other hand, a breach of a treaty, however serious, does not ipso facto put an end to the treaty, and it is not open to the injured State simply to allege a violation of the treaty and pronounce the treaty at an end.21 As such, Article 60, rather than envisaging reprisals, aims at restoring the contractual balance. The principles stated therein follow from the reciprocity of the rights and duties of States and correspond to the rule pacta sunt servanda (Article 26, N. 9).22

6According to Article 60, the innocent party may invoke the breach as a ground for suspending or terminating the treaty (N. 9); conversely, the innocent party may equally allow the treaty to continue in force and to assert its right to performance of the treaty.23 The options of suspension or termination avert the danger of the defaulting State enforcing the treaty against the innocent party while itself violating it.24 However, the innocent party may choose to demand resumption of performance of the treaty from the defaulting party which cannot, therefore, by its breach, force the termination or suspension of the treaty.25 In all cases, Article 60 does not require the consent of the defaulting State and leaves the final deci-

19See the statement in the ILC by Bartos, YBILC 1966 I/2 64, para. 77.

20See the ILC Report 1966, YBILC 1966 II 254 f, para. 6; Feist, Kündigung 135.

21Ibid. 254, para. 5.

22See the statements in the ILC by de Luna, YBILC 1963 I 128, para. 3, and YBILC 1966 I/2 62, para. 64; and in Vienna by the Venezuelan delegation, OR 1968 CoW 352, para. 62; also Verdross/Simma N. 811.

23Statement in Vienna by the Expert Consultant, Sir Humphrey Waldock, OR 1968 CoW 359, para. 71. Third States are also entitled to reactions, see subparas. 2(a)(ii) and 2 (c), (N. 19, 22).

24ILC Report 1966, YBILC 1966 II 255, para. 7.

25Particularly if the innocent party performed first. See the sep. op. of Judge Jiménez de Aréchaga in the ICAO Council Jurisdiction (India/Pakistan) Case, ICJ Reports 1972 147; Capotorti, RC 134 (1971 III) 551. But see the BP v. Libyan Arab Republic Arbitration, ILR 53 (1979) 333, and passim.

party which contributed to the breach cannot have a right to invoke Article 60.31 In particular, the injured party is not empowered unilaterally to suspend or terminate the treaty. Rather, it has the right to seek the peaceful

26T he ICJ in the Namibia Advisory Opinion, ICJ Reports 1971 49, para. 101.

27See the statement in Vienna by the US delegation, OR 1968 CoW 354, para. 8, according to which it may be disproportionate for the innocent State to consider termination of the treaty where there are circumstances excusing the breach of treaty.

28T his is confirmed by subparas. 2(b) and (c) which, in comparison with para. l and subpara. 2(a), strike a balance between communal and individual interests by permitting only suspension. See the ILC Report 1966, YBILC 1966 II 255, para. 7; Waldock Report V, ibid. 36, paras. 3 and 4.

29See the statement in the ILC by Waldock, YBILC 1966 I/2 59, para. 19.

30Namibia Advisory Opinion, ICJ Reports 1971 46. In the Gabcikovo-Nagymaros (Hungary/Slovakia) Case, the Court noted that Hungary had by its own conduct prejudiced its right to terminate the treaty at issue, ICJ Reports 1997 67, para. 110. See the 1985 Memorandum of the Swiss Government according to which participation as arbitrator in a treaty dispute did not imply that Switzerland was a “party” to the treaty, SJI R 42 (1986) 117 f.

31Gomaa, Suspension 123, 129 f.

settlement of the dispute as required by Article 33 of the UN Charter and, more particularly, to follow the procedures of Articles 65–68 (q.v.).32

In light thereof, the Namibia Advisory Opinion (N. 27) appears too categorical inasmuch as, in the context of Article 60, reference is made to a “general principle of law that a right of termination on account of breach must be presumed to exist in respect of all treaties”.33

For Sinclair, this manner of proceeding in Article 60 is unsatisfactory since the aggrieved party is obliged to continue compliance with a treaty which the other party is violating, while the often protracted procedure of dispute settlement is in progress.34 In the ILC, Verdross complained that the provision was mixing up rules of substance and of procedure.35

c) “Suspension” or “Termination” of the Treaty

9The innocent State has the possibility of invoking the breach as a ground for suspending or terminating the treaty. The suspension of treaty provisions does not a ect the treaty regime itself, but releases temporarily the innocent and the defaulting parties from the performance of treaty obligations (Article 72, q.v.) until the latter party carries out its obligations.36 The termination of the treaty brings the entire regime to an end (Article 70, q.v.). Where alternatives are possible, as under para. 1 or subpara. 2(a), the principle of proportionality calls for the option of suspension to be considered first.37

d) “In Whole or in Part”

10Article 60 assumes that treaty provisions are in principle separable. Thus, the suspension of a treaty as in paras. 1 and 2 may concern that treaty in whole or in part. (Note that the separability of treaty provisions in such cases is not governed by Article 44, N. 11.) If the innocent party contemplates suspension, this may concern the entire treaty, parts of it, or solely individual provisions, in which case all other provisions remain operative. The final decision lies within the discretion of the innocent party which will consider the relevance of the provisions in context of the treaty, the nature

32See the ILC Report 1966, YBILC 1966 II 254 f, para. 6; Aust, Modern Treaty Law 293. Plender, BYBIL 57 (1986) 160 , 163 f, advocates (at least) the direct right of the injured part unilaterally to suspend the treaty.

33ICJ Reports 1971 47; on this, see Briggs, AJIl 68 (1974) 55 (“most unfortunate”); Hempel et al. v. Attorney General Case, Australian LR 77 (1987) 670 (“before the innocent party is entitled to terminate, the breach must be a material one”, italics added ); Gomaa, Suspension 98.

34Vienna Convention 188.

35YBILC 1966 I/2 63, para. 75.

36See Waldock in the ILC, YBILC 1963 I 132, para. 35.

37Waldock in the ILC, YBILC 1966 I/2 65, para. 7; contra Gomaa, Suspension 120 (no requirement of proportionality).

of the breach, generally the principles of good faith and proportionality, and the interests of other parties.38

A State breaching a provision of a general multilateral treaty may be unconcerned by the possible suspension of that particular provision by the other parties. The latter, however, have the possibility of suspending the operation of additional, or even all, provisions of the treaty.39 This possibility o ers the innocent States considerable flexibility and, hence, potentially provides them with an “e ective remedy”.

A strictly textual interpretation of Article 60 discloses a consistent distinction made in this respect in para. 1 and subpara. 2(a) between termination tel quel, on the one hand, and suspension “in whole or in part”, on the other. The German translation is particularly telling in this respect.40 This leads to the conclusion that according to Article 60 termination necessarily a ects the entire treaty.41

3. No Direct E ects (Articles 65–68)

The innocent party may not unilaterally and directly suspend or terminate 12 the treaty. Article 60 provides that that party is merely entitled to invoke the breach as a ground for these courses of action (N. 8). Articles 65–68 (q.v.) postulate, and both the travaux préparatoires42 and subsequent developments confirm (the latter to a lesser extent, N. 29), that the innocent party must pursue its rights within the framework provided by Articles 65–68, and

that suspension and termination are merely the results of these procedures. Logically, Article 60 does not even permit immediate provisional suspension. Exceptionally, subpara. 2(a) provides for direct action (N. 18).43 The framework of Articles 65–68 thus establishes a balance between the

38See statement in Vienna by the Expert Consultant, Sir Humphrey Waldock, OR 1968 CoW 237, para. 40; Verdross/Simma N. f; Capotorti, RC 134 (1971 III) 551.

39See Waldock in the ILC, YBILC 1966 I/2 65, para. 5.

40I.e., “Grund für die Beendigung des Vertrags oder für seine gänzliche oder teilweise Suspendierung” (italics added ).

41Gomaa, Suspension 120 (with further references); the statement by Rosenne of the Israeli delegation in Vienna, OR 1969 Plenary 167 f, para. 30: “it was his delegation’s understanding that the meaning of the introductory phrase in paragraph 2(a) . . . was that the other parties might by unanimous agreement suspend the operation of the treaty in whole or in part or terminate it in whole or in part”; and in the ILC, YBILC 1966 I 294, para. 63.

42ILC Report 1966, YBILC 1966 II 254 f paras. 5 ; the statement by the Chairman of the Drafting Committee in Vienna (Yasseen), OR 1968 CoW 478, para. 23; the rejection of the Venezuelan amendment, ibid. 359, paras. 79 ; the statement by Briggs in the ILC, YBILC 1966 I/2 61, para. 45.

43But see Aust, Modern Treaty Law 294 (1) ; Kirgis, Cornell ILJ 22 (1989) 566 f, 371.

competing interests in Article 60 and provides important safeguards against abuse.44

4. What Constitutes a Material Breach? (Para. 3)

13Subparas. 3(a) and (b) define a material breach narrowly and exclusively (N. 14–16), though the provisions were intended to grant some flexibility.45 The grounds mentioned therein may be invoked simultaneously.46 Culpa of the defaulting State is not mentioned as a requirement. The innocent State should relate its subsequent courses of action to the treaty containing the violated treaty provisions.47

14Subpara. 3(a) mentions the special case of a repudiation of the treaty not sanctioned by the present Convention. In this case, the defaulting State rejects the treaty as a whole. Repudiation encompasses denunciations not justified by the Convention (in particular Articles 42–63, q.v.) or excessive retaliatory measures, though not legitimate reprisals or courses of action under Article 60.48

15Subpara. 3(b) focuses more generally on the violation of a provision essential to the accomplishment of the object and purpose of the treaty. A typical example of such a violation would be the non-performance, or the incorrect performance, of certain treaty provisions. In fact, it is not the provisions themselves, but their function within the treaty regime, which Article 60 requires to be essential.49 Any object or purpose of the

44ILC Report 1966, YBILC 1966 II 254 para. 5; the observation by the UK Government to the ILC, YBILC 1966 II 34.

45See the ILC Report 1966, ibid. 255, para. 9; the statement in Vienna by the Expert Consultant, Sir Humphrey Waldock, OR 1968 CoW 358, para. 70; the early definitions of a material breach in Waldock Report II, YBILC 1963 II 73. Also the statements in the ILC by Briggs, YBILC 1963 I 123, para. 13; and Castrén, ibid. 128, para. 78; Schwelb, IJIL 7 (1967) 315.

46Namibia Advisory Opinion, ICJ Reports 1971 47, para. 95.

47Di erently Simma, ÖZöR 20 (1970) 56, and in Festschrift von der Heydte 627, for the case of interdependent treaties. See also Pakistan in the Jurisdiction Council Case, ICJ Pleadings 1973 649 . As to the relevance of ancillary documents, see the Memorandum of the Legal Adviser of the US Department of State, cited in Glennon/Franck II 212, 221.

48See the ILC Report 1966, YBILC 1966 II 255 para. 9; Capotorti, RC 121 (1971 III) 550 f; see also Article 42 and N. 26 below. Originally, the ILC employed the term “unfounded repudiation”; but see the statement in the ILC by Waldock, YBILC 1966 I/2 64, para. 3.

49Di erently Hutchinson, BYBIL 59 (1988) 196: “[i]nterpreted literally, this does not require that the breach actually has the e ect of frustrating the achievement of that aim”.

treaty may be considered.50 Indeed, the “object and purpose”-test enables consideration of various types of treaties (see Article 31, N. 11–14). Mere provocation by a State does not count as a breach, there must be some concrete adverse e ect.51 T he violation of other rules, namely of general international law, is not covered by subpara. 3(b).52

Subpara. 3(b) requires a material, not a fundamental or major breach of a 16 provision a ecting the central purposes of the treaty. A provision viewed by

a party as essential to the e ective execution of the treaty is material, if it induced that party to enter into the treaty at all, even though the provision may be of an ancillary character.53 For instance, even the performance of an arbitration clause may be regarded as essential.54 Conversely, subpara. 3 (b) does not raise the issue of minor breaches of essential provisions,55 it only asks whether a (major or minor) breach a ects the accomplishment of the object or purpose of the treaty. At any rate, these criteria depend on the subjective judgment of the innocent parties.56

5. Breach of Bilateral Treaties (Para. 1)

Article 60 distinguishes in paras. 1 and 2 between di erent types of treaties. 17

Para. 1 concerns the material breach of a bilateral treaty. In this case, the injured party is entitled to invoke the breach (N. 8) as a ground for terminating the treaty as a whole or for suspending its operation in whole or in part (N. 9).

50On the object and purpose, see Crnic-Grotic, Asian YBIL 7 (1997) 170 .

51Waldock in the ILC, YBILC 1966 I/2 65, para. 6. See the situation of a “premature breach” in the Gabcikovo-Nagymaros (Hungary/Slovakia) Case, ICJ Reports 1997 65, para. 105.

52T he Gabcikovo-Nagymaros Case, ibid.; di erently Verdross/Simma N. 815 at n. 38.

53ILC Report 1966, YBILC 1966 II 255, para. 9; Aust, Modern Treaty Law 239; Capotorti, RC 121 (1971 III) 551 f; Schwelb, IJIL 7 (1967) 313; Kirgis, Cornell ILJ 22 (1989) 555.

54Article 20, subpara. 2(c) of Waldock Report II, versus the Uruguayan delegate in Vienna ( Jiménez de Aréchaga), OR 1968 CoW 356, para. 39.

55Diferently Simma, ÖZöR 20 (1970) 61; Schwelb, IJIL 7 (1967) 314 f. For the consequences of non-material breaches, see Jennings, RC 121 (1967 II) 566.

56See the Austrian Government in ÖZoR 27 (1976) 347; the statement by Yasseen in the ILC, YBILC 1963 I 25, para. 39.

6. Breach of Multilateral Treaties (Para. 2)

a) Unanimous Agreement of the Other Parties (Subpara. 2[a])

18Para. 2 covers multilateral treaties. Subpara. 2(a) stipulates the right of the innocent parties to react jointly to the breach, for instance, if confronted with a persistent treaty-breaker whom they wish to expel from the treaty.57

This provision authorises all other parties by unanimous agreement to suspend the operation of the treaty in whole or in part or to terminate it (N. 9). The innocent parties can do so either in the relations between themselves and the defaulting State (subpara. 2[a][i]), in which case the treaty remains in operation between the innocent States inter se; or they can do so as between all the parties (subpara. 2[a][ii]), in which case it is agreed that the treaty ceases to exist erga omnes. Unanimity does not include the defaulting State.58 The agreement may correspond with the notion of a “treaty” in Article 2, subpara. 1(a) (q.v.), but, as in Article 31, para. 2 (q.v.), the term is wider and covers any contractual instrument including, in particular, agreements not in written form.59 This right of the innocent parties is not subject to the procedures in Articles 65–68. Thus, the parties need not “invoke” the breach, they can proceed to immediate action (N. 12). In practice, considerable di culties may be encountered when attempting to obtain the “agreement” of the other parties on the material breach as well as on the suspension or termination of the treaty.60

It has been criticised that subpara. 2(a) is novel and may result in an “unjustified abrogation”61 of the treaty. This overlooks that unanimity is a rigorous condition;62 and that the parties (admittedly excluding the defaulting State) are obviously masters of their own treaty.63

b) Position of Specially A ected Parties (Subpara. 2[b])

19Subpara. 2(a) proceeds from the assumption that, if a multilateral treaty is breached by one party, in principle that breach will a ect the interests of all other parties.64 By being a party to a multilateral treaty, a State has a general interest in the observance of the treaty by all the parties. Nevertheless, subpara. 2(b), which may be invoked independently of subpara. 2(a),65

57Statement by Waldock in the ILC YBILC 1966 I/2 65, para. 7.

58Waldock in the ILC, YBILC 1963 I 247, para. 126.

59See also Article 39, N. 7. Di erently Hutchinson, BYBIL 59 (1988) 289.

60Neff, BYBIL 59 (1988) 189.

61Simma, ÖZoR 20 (1970) 66; Sinclair, Vienna Convention 188; the statement in Vienna by the Australian delegation, OR 1968 CoW 358, para. 64.

62See the statement in Vienna by the Israeli delegation (Rosenne), OR 1969 Plenary 113, para. 34, 167 f, para. 30.

63Verdross/Simma N. 813.

64See the statement in the ILC by Rosenne, YBILC 1966 I/2 60, para. 26.

65Jiménez de Aréchaga, RC 159 (1978 I) 83.

provides a further di erentiation. It envisages that a party may be specially affected in that it has a particular interesting seeing that another party fulfils towards it the obligations laid down in the treaty and, accordingly, a special interest in reacting to a breach of treaty by that party.66

So-called “law-making” treaties—for example the Convention itself, or the 1961 and 1963 Vienna Conventions on diplomatic and consular relations—may regulate in multilateral form what are essentially bilateral relations between the parties. In the case of such treaties, there is both a general interest of all the parties in the observance of the treaty, and a particular interest of each party in seeing that its own rights under the treaty are respected.67

Accordingly, subpara. 2(b) entitles the party specially a ected by the 20 breach to invoke it (N. 8) as a ground for suspending the operation of

the treaty, in whole or in part (N. 9), in the relations between itself and the defaulting State. The provision does not go so far as to grant the specially a ected State the right unilaterally to terminate or withdraw from the treaty which, particularly in the case of law-making treaties, might jeopardise the security of the rights and obligations of the other parties as between themselves. In order to avoid an abuse of rights in subpara. 2(b), the “specially a ected” State will be expected to demonstrate its special position.68

c) Situation of Radical Change of Parties’ Position (Subpara. 2[c])

Subpara. 2(c) goes beyond the bilateral relations envisaged in subparas. 21 2(a) and (b) (N. 18–20) and concerns certain multilateral treaties which

are of such a character that a material breach of the treaty’s provisions by one party radically changes the position of every party with respect to the further performance of its treaty obligations. Subpara. 2(c) has so-called integral treaties in mind, e.g., on disarmament, where a breach by one party tends to undermine the whole regime of the treaty as between all the parties.69 In such a case, a State cannot individually suspend the treaty vis-à-vis the defaulting State (as in subpara. 2[b], N. 20) without generally violating its obligations towards the others, and yet will be in need of protection, particularly if the agreement in subpara. 2(a) (N. 18)

66Waldock in the ILC, 1966 I/2 64, para. 4. Subpara. 2(a) does not go so far as to require “rights” of the State concerned; but see de Luna in the ILC , YBILC 1966 I/2 63, para. 70.

67Yasseen, ibid. 62, para. 55.

68On this para., see the ILC Report 1966, YBILC 1966 II 255, para. 7; Waldock Report V, ibid. 36, para. 3; the statements in the ILC by Rosenne, YBILC 1966 I/1 60, paras. 26, 28 ; and Briggs, ibid. 61, paras. 47 f; but see Yasseen, ibid. 62, para. 55.

69Accordingly, in subpara. 2(c), the position of every party must be radically a ected; see also Verdross/Simma N. 813; Klein, Statusverträge 234 .

does not eventuate.70 As a result, any State is entitled to invoke the breach as a ground for suspending the operation of the treaty in whole or in part with respect to itself. As in subpara. 2(b) (N. 20), no agreement of the other parties is required here for the State to suspend the operation of the treaty with respect to itself generally in its relations with all other parties.

7. Specific Treaty Provisions (Para. 4)

22According to para. 4, paras. 1–3 are without prejudice to any provision in the treaty applicable in the event of a breach. Provisions in a specific treaty on substantive issues in Article 60 or on the procedures in Articles 65–68 (q.v.) will have priority over the Convention rules which remain residual and constitute leges generales.71 Those other provisions will have priority even if that treaty itself is being suspended or terminated on account of a breach.72 Conversely, Articles 60 and 65–68 will apply if the procedural provisions of that treaty have been violated.

8.Humanitarian Treaties (Para. 5)

23Para. 5, introduced in Vienna in 1969 (N. 4), concerns treaty provisions relating to the protection of the human person contained in treaties of a humanitarian character. This provision—the only one in the Convention concerning the human person (sixth preambular para., Preamble, N. 13)— relates to multilateral conventions such as the 1949 Geneva Conventions and the 1977 Additional Protocols.73 Paragraphs 1 to 3 do not apply to

70See the ILC Report 1966, YBILC 1966 II 255, para. 8; the statements in the ILC by

Waldock, YBILC 1966 I/1 65 f, para. 14; Castren ibid. 129, para. 21, regarding demilitarisation and neutrality treaties; and Rosenne ibid. 60, para. 24 (“highly subjective element”).

71See the ILC Report 1966, YBILC 1966 II 255, para. 10; the situation in the Gab- cikovo-Nagymaros (Hungary/Slovakia) Case, ICJ Reports 1997 62 f, para. 100; in the Fisheries Jurisdiction (UK/Iceland) Case, ICJ Reports 1973 21, the Court regarded the invocation of procedures between the parties as su cient for the application of Article 60 of the Convention and, hence, Articles 65–68 as dispositive; also in the Namibia Advisory Opinion, ICJ Reports 1971 47, para. 96. See also Waldock Report II, YBILC 1963 II 75, para. 10; Verdross/Simma N. 817; Simma, ÖZöR 20 (1970) 82, and in

Festschrift von der Heydte 627 f.

72 T he ICJ in the ICAO Council Jurisdiction (India/Pakistan) Case, ICJ Reports 1972 53 f, 64 f; Capotorti, RC 134 (1971 III) 534.

73T he principle in para. 5 was referred to in the Namibia Advisory Opinion, ICJ Reports 1971 47, 96, and at 55 para. 122. See also the sep. op. of Judge Parra-Aranguren in the Application of the Convention on the Prevention and Punishment of the Crime of Genocide (Bosnia and Herzegovina/Yugoslavia) (Preliminary Objections) Case, ICJ Reports 1996 656 f, in respect of the Genocide Convention: in the Prosecutor v. Martic (Rule 61)

the provisions in these conventions. Thus, in case of a breach of such a treaty, the innocent States are not entitled to invoke the breach as a ground for suspending or terminating the treaty as in paras. 1–3, as this would invariably deprive the individuals of their protection under the treaty. By way of example (and emphasis), para. 5 refers in particular to provisions prohibiting any form of reprisals against persons protected by such treaties as a reaction to a breach of the treaty.

In Vienna it was suggested that para. 5 amounted to a “saving clause”,74 24 ensuring that a breach of treaty did not a ect the parties’ customary obligations (Article 43, q.v.).75 As a rule, humanitarian treaties are indeed declaratory of customary law, and in this respect para. 5 and Article 43

will indeed coincide.76 However, para. 5 plays an additional part on the contractual level, where it addresses so-called non-reciprocal treaties which create rights, not among the States parties, but in favour of individuals and irrespective of the conduct of the parties in relation to each other.77

While human rights treaties constitute such non-reciprocal treaties, it is doubtful whether they fall within para. 5, which refers distinctly (and restrictively) to humanitarian treaties.78 The question nevertheless appears moot in that States parties to both universal and regional human rights treaties in fact apply the principles of para. 5 in their relations with each other under these treaties, namely by resorting to the relevant judicial or other supervisory procedures when confronted with allegations of a breach of treaty.

Case of the ICTY, ILR 108 (1997) 45, para. 9. On the subject also Gomaa, Suspension 106 ; J. Daniel, La Convention de Vienne de 1969 sur le droit des traités et le droit humanitaire, Revue internationale de la Croix-Rouge 1972 410 .

74See the statement in Vienna by Rüegger of the Swiss delegation, OR 1969 Plenary 112, para. 22.

75See the statements in Vienna by the Expert Consultant, Sir Humphrey Waldock, OR 1968 CoW 359, para. 76, according to whom “problems of that kind” were covered by Article 43 (q.v.); and by the Greek and Swiss delegations, ibid. 113, para. 43, and 115, para. 116, respectively.

76Hence, the issue of the intertemporal application of para. 5 does not arise; but see Gomaa, Suspension 112.

77E.g., the 1978 judgment of the European Court of Human Rights in the Ireland v. United Kingdom Case, Series A no. 25, 90 f, para. 239 (“unlike international treaties of the classic kind, the Convention comprises more than mere reciprocal engagements between contracting States. It creates, over and above a network of mutual, bilateral undertakings, objective obligations which . . . benefit from a ‘collective’ enforcement”); also Aust, Modern Treaty Law 295.

78As proposed, for instance, by Aust, ibid.; Sinclair, Vienna Convention 190; Schwelb, AVR 16 (1974/75) 14 ; Simma, Festschrift von der Heydte 625, sees a general exception in Article 60 regarding (non-reciprocal) human rights treaties. See for an early document the commentary to Article 19 of Fitzmaurice Report II, YBILC 1957 II 54, para. 125.

C.CONTEXT

1.Relationship to Other Provisions

25The relationship of Article 60 to various other provisions has been discussed above, for instance to Article 43 in respect of customary law (N. 24), to Articles 65–68 on the procedure to be followed (N. 8, 12, 13), to Article 70 on termination (N. 9), and to Article 72 on suspension (N. 9). References to Article 60 can be found in Articles 30, para. 5, Article 44, para. 2, and Article 45 (q.v.).

Article 45 (q.v.) requires that States react within a reasonable period of time after obtaining knowledge of the breach. The principle underlying this provision (qui tacet consentire videtur) would also appear to cover the situation where a State claiming to be the victim of a breach of treaty, actually induced the other State to commit the violation.79

2. Matters Not Dealt With

26Article 60 does not address the question whether a party has the right to take reasonable countermeasures, or to present an international claim for compensation, since these matters are governed by the rules on State responsibility which, according to Article 73 (q.v.), remain outside the Convention.80 Indeed, there is nothing to prevent the injured State from claiming compensation instead of, or in addition to, exercising its rights under Article 60.81 Furthermore, Article 60 does not answer the question whether the injured party is entitled to invoke the breach of a treaty as a ground for suspending or terminating other treaties between itself and the defaulting party.82 There is also no discussion of less than material breaches.83 Finally, it has been argued above that para. 5 of Article 60 does not apply to non-reciprocal human rights treaties (N. 24).

79See de Luna in the ILC, YBILC 1963 II 121, para. 78.

80On the topic Ch. Dominicé, The International Responsibility of States for Breach of Multilateral Treaty Obligations, EJIL 10 (1999) 353 ; P.-M. Dupuy, Droit des traités, codification et responsabilité international, AFDI 43 (1997) 9 .

81Aust, Modern Treaty Law 293; Akehurst, EPIL 4 (2000) 988; Fitzmaurice, Austrian RIEL 6 (2001) 11 .

82Verdross/Simma N. 816.

83L.F. Damrosch, Retaliation or Arbitration—or Both? The 1978 US-France Aviation Dispute, AJIL 74 (1980) 790.

3. Customary Basis of Article 60

State practice discloses a growing recognition by States of the customary 27 nature of Article 60, at least with regard to bilateral treaties.84 Practice on multilateral treaties is sparse, and the distinction between the e ects of breaches of bilateral and multilateral treaties has not always been accepted. Moreover, States are not always consistent in their attitudes as to whether a breach of treaty should bring about direct e ects; or whether the procedures

of Articles 65–68 should first be complied with. As regards the practice of courts, it is submitted that the few cases dealing with Article 60 are actually less conclusive for our purposes than it would appear.85

In the 1971 Namibia Advisory Opinion, the question arose whether UN GA Res 2145 (XXI) of 27 October 1966 was ultra vires. In that Resolution, the UN General Assembly had declared that South Africa had failed to fulfil its obligations as a mandatory power in Namibia and had disavowed the mandate, for which reason the latter was terminated. The Court considered that “[t]he rules laid down by the [Convention] concerning termination of a treaty relationship on account of breach may in many respects be considered as a codification of existing customary law on the subject”.86 The Court concluded that in casu both forms of material breach in Article 60, subparas. 3(a) and (b), had occurred and that Res 2145 amounted to an exercise of the right of termination.87

However, the usefulness of this Advisory Opinion is diminished by the fact it concerned a relationship with bilateral connotations (as in Article 60, para. l, N. 17) and not the more complex (and traditionally more unsettled) situation of a breach of a multilateral treaty.

In the 1973 BP v. Libyan Arab Republic Arbitration, Single Arbitrator Lagergren found that the Libyan nationalisation laws constituted a fundamental violation of the concessions at issue.88 With respect to the question of the continuing existence of the concession, the Arbitrator stated, with reference to Article 60 (which he regarded as codificatory): “a breach of treaty, regardless of how serious it is, does not ipso facto terminate the treaty and . . . a State is not at liberty simply to state that a breach of treaty has occurred and that the treaty as a consequence is terminated . . . The . . . rule should be understood merely as authorizing—and requiring—a formal declaration to the e ect that performance under the treaty by the party not in default will come to an end”.89

Lagergren concluded that Article 60 “[fell] short of providing that the innocent party is entitled to demand specific performance” of the violated treaty.90 Moreover,

84See Villiger, Customary International Law 365 .

85Ibid. 367 . See the Gabcikovo-Nagymaros (Hungary/Slovakia) Case, where the Court regarded Article 60 “as a codification of existing customary law”, ICJ Reports1997, 62, para. 99, also 38, para. 46.

86Ibid. 47, para. 95, and 46.

87Ibid. para. 95.

88ILR 53 (1979) 329.

89Ibid. 333.

90Ibid.

there did “not exist a uniform general principle of law that an agreement continues in e ect after having been repudiated by one party but not by the other”.91

This restrictive interpretation of Article 60 focuses on the termination of a treaty as a result of its breach and not on the right of the innocent party to opt for the continuing performance of the treaty obligations. However, the case concerned a concession and the law was determined, inter alia, on the basis of a general principle of law as expressed in municipal legal systems.

28Authors are not unanimous in their assessment of the declaratory nature of Article 60.92 Some implicitly regard the provision as codificatory, often with reference to the Namibia Advisory Opinion.93 Most writers, however, see the main principle in Article 60 as being established in general international law, but many details as new;94 often, reference is made to para. 2 and the link to Articles 65–68 as the innovative part.95 Simma’s studies of Article 60 have inferred from a comparison with the pre-ILC situation and from some comments of ILC members that Article 60 amounts to a progressive development of pre-existing customary law.96

29In sum, it is doubtful whether Article 60 as a whole is declaratory of customary law. Only para. 1 on bilateral treaties presents a clear and well established picture. With regard to paras. 2 and 3, the ILC had some difficulties in arriving at a generally suitable compromise. Since l969, States and courts have repeatedly a rmed the declaratory nature of Article 60, but the practice concerning multilateral treaties is sparse and not always convincing. The relationship between Article 60 and Articles 65–68 remains unsettled. As a result, it appears that the 1968/1969 Vienna Conference may well have stimulated the generation of new customary rules embodied in paras. 2 and 3. Yet State practice must still accumulate and become more consistent before these rules can be regarded as settled.

91Ibid. 352; also 356.

92See Villiger, Customary International Law 369, N. 543.

93Inter alia, Elias, Law of Treaties 114 ; Jiménez de Aréchaga, RC 159 (1978 1) 79 .

94Capotorti, RC 134 (1971 III) 548 f n. 90, and Simma, ÖzöR 20 (1970) 35 , see in the principle inadimplenti non est adimplendum a general principle of law; Gomaa, Suspension 99.

95Fitzmaurice, Austrian RIEL 6 (2001) 3 (“one of the most challenging and complicated issues of the law of treaties”); Capotorti, ibid. 553; Haraszti, Some Fundamental Problems 317 f; Verdross/Simma N. 813; Akehurst, EPIL 4 (2000) 998; Klein, Statusverträge 228.

96ÖZöR 20 (1970) 58 f; Festschrift von der Heydte 618; in GYBIL 21 (1978) 79, Simma regards as new the limitations in paras. 1 and 2 of the right of suspension, para. 3, and the link with Articles 65–68; most recently Simma/Tams, Article 60, N. 6–10.

Article 61