Jochen A Frowein
- Peremptory norms / ius cogens — Customary international law — State practice — Vienna Convention on the Law of Treaties — Treaties, invalidity, termination, suspension, withdrawal
Published under the auspices of the Max Planck Foundation for International Peace and the Rule of Law under the direction of Rüdiger Wolfrum.
1 Many legal systems make the distinction, well-known in Roman law, between ius strictum and ius dispositivum . While parties may disregard rules of ius dispositivum in their contractual relationships, their legal acts must comply with the ius strictum , otherwise they are void or at least not completely valid. Arts 53 and 64 of the Vienna Convention on the Law of Treaties (1969) (‘VCLT’) have formally recognized that the same distinction exists in public international law. Art. 53 VCLT reads: A treaty is void if, at the time of its conclusion, it conflicts with a...