Angående Ukrainas ansträngningar att få bort Ryssland ur säkerhetsrådet, som ni säkert hört om - då Sovjet kollapsade så fortsatte ju Ryssland bara i Sovjets namn - så står det så här i FN:s stadgar:
https://www.un.org/en/about-us/un-charter/full-text
Urklipp, för de som inte orkar läsa hela häftet:
Chapter V: The Security Council
Article 23
1. The Security Council shall consist of fifteen Members of the United Nations. The Republic of China, France,
the Union of Soviet Socialist Republics, the United Kingdom of Great Britain and Northern Ireland, and the United States of America shall be permanent members of the Security Council. The General Assembly shall elect ten other Members of the United Nations to be non-permanent members of the Security Council, due regard being specially paid, in the first instance to the contribution of Members of the United Nations to the maintenance of international peace and security and to the other purposes of the Organization, and also to equitable geographical distribution.
Chapter XIX: Ratification and Signature
Article 110
3. The present Charter shall come into force upon the deposit of ratifications by the Republic of China, France,
the Union of Soviet Socialist Republics, the United Kingdom of Great Britain and Northern Ireland, and the United States of America, and by a majority of the other signatory states. A protocol of the ratifications deposited shall thereupon be drawn up by the Government of the United States of America which shall communicate copies thereof to all the signatory states.