The Articles 52 and 53 of the 1969 Vienna Convention on the Law of Treaties provide that treaties whose adoption has been procured by the threat or use of force are void.
Article 52: Coercion of a State by the threat or use of force
A treaty is void if its conclusion has been procured by the threat or use of force in violation of the principles of international law embodied in the Charter of the United Nations.
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 recognized 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.
The prohibition against the international use of force embodied in Article 2 paragraph 4 of the United Nations Charter is a universally recognized rule of jus cogens in general international law .
Article 2 paragraph 4
United Nations Charter, Article 2
The Organization and its Members, in pursuit of the Purposes stated in Article 1, shall act in accordance with the following Principles.
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(4) All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations.
Donald Trump has suggested to Volodymyr Zelensky, the president of Ukraine, that he get together with Vladimir Putin to work out the differences between the two countries.
President Trump: And I really hope that Russia — because I really believe that President Putin would like to do something. I really hope that you and President Putin get together and can solve your problem. That would be a tremendous achievement. And I know you’re trying to do that.\–President Donald J. Trump, Remarks before bi-lateral meeting with Ukrainian President Volodymyr Zelensky, New York, September 25, 2019.
Any treaty concluded between Zelensky and Putin, so long as Russian forces occupy the Crimea, and continue their aggression in the Eastern Ukraine (Donbas) provinces of Donetsk and Luhansk, would be completely void in view of Articles 52 and 53 of the Vienna Convention on the Law of Treaties, and the jus cogens principle of general international law embodied in Article 2 paragraph 4 of the United Nations Charter.
See also:
“Russia’s utter and continuing violation of international law in the Ukraine: U.N. General Assembly Resolution A/RES/25/2625 (1970) on Principles of International Law and Friendly Relations Among States,”The Trenchant Observer, February 8, 2015.
“The Great Buffoon’s lack of support of Article 2(4) of the U.N. Charter,” The Trenchant Observer, August 27, 2019.
“Reports that Merkel is negotiating a settlement with Putin that would recognize Russian annexation of the Crimea, in violation of peremptory norms of international law,” The Trenchant Observer, August 6, 2014.
The Trenchant Observer