Revista Temas de Derecho Constitucional

330 Revista Temas de Derecho Constitucional “Article 67. Instruments for declaring invalid, terminating, withdrawing from or suspending the operation of a treaty. 1. The notification provided for under Article 65, paragraph 1 must be made in writing. 2. Any act declaring invalid, terminating, withdrawing from or suspending the operation of a treaty pursuant to the provisions of the treaty or of paragraphs 2 or 3 of Article 65 shall be carried out through an instrument communicated to the other parties. If the instrument is not signed by the Head of State, Head of Government or Minister for Foreign Affairs, the representative of the State communicating it may be called upon to produce full powers. Article 68. Revocation of notifications and instruments provided for in Articles 65 and 67. A notification or instrument provided for in Article 65 or 67 may be revoked at any time before it takes effect.” 53 The VCLT constitute the most significant piece of international legislation. In terms of modern tools and state practice available in this area, some treaties provide for sunset clauses stipulating a period during which States can retract their intention to denounce a treaty. It is important to distinguish between a denunciation, withdrawal, and termi- nation of a treaty pursuant to its terms from the termination or suspension of a treaty due to supervening impossibility or fundamental change of circumstances which would include, for instance, an expulsion or suspension clause concerning membership. 54 Withdrawal from a treaty is a unilateral act which entails also a political stance taken by States on particular issues. Although clear in its formulation, the wording of the articles is no self-explanatory. Revocation of the withdrawal is conceived in the preliminary ruling as a unilateral act per se, confirming the unilateral revocability of Article 50. Notification is a unilateral act under international law. As such, it becomes effective once all the requirements for ef- fective external action by a sovereign state have been fulfilled. This is usually the case, if the respective state organ is authorised to act this way. 55 It follows that the reversal of the notification consists also of unilateral act as argued by the Court. In its analysis, the Court precisely emphasised the sovereignty of the withdrawing Member State. 53 VCLT, Articles 65-68. 54 In a review of the literature on the design and use of treaty derogation clauses see, among others: LR Helfer, ‘Flexibility in International Agreements’ in J Dunoff and M Pollack (eds), International Law and International Relations: Taking Stock: Synthesizing Insights from Interdisciplinary Scholarship (CUP, Cambridge 2012); R. Helfer, Chapter 25 Terminating Treaties, in The Oxford Guide to Treaties (Duncan Hollis, ed., Oxford University Press, 2012), pp. 634-650 available at https://scholarship.law.duke.edu/cgi/viewcontent.cgi?articl e=5338&context=faculty_scholarship; Stephen P. Mulligan, Withdrawal from International Agreements: Legal Framework, the Paris Agreement, and the Iran Nuclear Agreement, May 4, 2018. Available at https://fas.org/ sgp/crs/row/R44761.pdf (accessed 30 December 2018); LR Helfer, ‘Exiting Treaties’ (2005) 91 Virginia L R at 1579, 1582 (explaining that ‘exit clauses create a lawful, public mechanism for a state to terminate its treaty obligations or withdraw from membership in an intergovernmental organization’); MM Gomaa, Suspension or Termination of Treaties on Grounds of Breach (Martinus Nijhoff, The Hague 1996) at pp. 167–8; S Rosenne, Breach of Treaty (Grotius, Cambridge 1985) 117–25; AE David, The Strategy of Treaty Termination: Lawful Breaches and Retaliations (Yale University Press, New Haven 1975) pp. 159–202 and Oliver Dorr and Kirsten Schmalenbach (eds), Vienna Convention on the Law of Treaties: A Commentary (Springer 2012). 55 See Article 7 VCLT, which applies – by analogy - to unilateral acts as well, see Fiedler, Unilateral acts in international law, in: EPIL IV (2000), 1021.