The Ministry of External Relations (MER) of the Union of Soviet Socialist Republics (USSR) was founded on 6 July 1923. It had three names during its existence: People's Commissariat for Foreign Affairs (1923–1946), Ministry of Foreign Affairs (1946–1991) and Ministry of External Relations (1991). It was one of the most important government offices in the Soviet Union. The Ministry was led by the 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.

In many countries, the ministry of foreign affairs is the highest government department exclusively or primarily responsible for the state's foreign policy and relations, diplomacy, bilateral, and multilateral relations affairs as well as for providing support for a country's citizens who are abroad. The entity is usually headed by a foreign minister or minister of foreign affairs. The foreign minister typically reports to the head of government.