The Ministry of External Relations (MER) of the Union of Soviet Socialist Republics (USSR) , formed on 16 July 1923, was one of the most important government offices in the Soviet Union. It was known as the People's Commissariat for Foreign Affairs , or Narkomindel, until 1946. The Ministry was known as the Ministry of Foreign Affairs , or MFA, from 1946 to 1991. The MER, at the all-Union level, was established on 6 July 1923, after the signing of the Treaty on the Creation of the USSR, and was based upon the People's Commissariat for Foreign Affairs of the Russian Soviet Federative Socialist Republic (RSFSR), formed in 1917. The Ministry was led by a Commissar prior to 1946, a Minister of Foreign Affairs prior to 1991, and a Minister of External Relations in 1991. Every leader of the Ministry was nominated by the Chairman of the Council of Ministers and confirmed by the Presidium of the Supreme Soviet, and was a member of the Council of Ministers.