Vienna Convention on Succession of States in respect of Treaties
The Vienna Convention on Succession of States in respect of Treaties is an international treaty promulgated in 1978 to set rules on succession of states. It was adopted partly in response to the "profound transformation of the international community brought about by the decolonization process".
Among its provisions it establishes that newly independent post-colonial states are subject to the "clean slate" rule, such that the new state does not inherit the treaty obligations of the colonial power (article 16).
This treaty has proven to be controversial largely because it distinguishes between "newly independent states" (a euphemism for former colonies) and "cases of separation of parts of a state" (a euphemism for all other new states).
Article 16 states that newly independent states receive a "clean slate", whereas article 34(1) states that all other new states remain bound by the treaty obligations of the state from which they separated. Moreover, article 17 states that newly independent states may join multilateral treaties to which their former colonizers were a party without the consent of the other parties in most circumstances, whereas article 9 states that all other new states may only join multilateral treaties to which their predecessor states were a part with the consent of the other parties.