The Soviet Union was formally dissolved and ceased to exist as a sovereign state and subject of international law on 26 December 1991 by Declaration No. 142-N of the Soviet of the Republics of the Supreme Soviet of the Soviet Union. It also brought an end to the Soviet Union's federal government and CPSU General Secretary Mikhail Gorbachev's effort to reform the Soviet political and economic system in an attempt to stop a period of political stalemate and economic backslide.