Any amendment to the West German Constitution was subject to (western) Allied permission, specific laws could be rejected, and the military governors could take over all governmental power in times of crisis. Those reservations were to be executed by the Allied High Commission of the three western allies, established on June 20 and claiming to exercise supreme state power within the former western zones of occupation. On November 22, 1949, Chancellor Konrad Adenauer signed the Petersberg Agreement, under which it was recognized that the sovereignty of West Germany remained limited.