The United Nations Security Council (UNSC) is a principal organ of the United Nations (UN), established in 1945 after World War II to succeed the League of Nations and address the problem of maintaining international peace and security. Its core mandate, outlined in Article 24(1) of the UN Charter, confers upon it the primary responsibility for the maintenance of international peace and security.
The UNSC is an institution composed of fifteen Members of the UN. This includes five permanent members (P5)—China, France, the Russian Federation, the United Kingdom, and the United States—who hold the power to veto any substantive resolution. The remaining ten non-permanent members are elected by the UN General Assembly for a two-year term, with five retiring each year, and are not eligible for immediate re-election. Decisions on non-procedural matters require an affirmative vote of nine members, including the concurring votes of all five permanent members, as per Article 27.
The Council's mechanism is defined by its powers under the UN Charter, particularly Chapter VI (Pacific Settlement of Disputes) and Chapter VII (Action with Respect to Threats to the Peace, Breaches of the Peace, and Acts of Aggression). Under Chapter VII, the UNSC can determine the existence of a threat to the peace (Article 39) and impose measures binding on all UN member states, such as economic sanctions or the authorization of military action.
The UNSC connects directly to the UN General Assembly, which elects the non-permanent members and receives annual reports from the Council. The Council's composition has changed only once since its inception: an amendment to the UN Charter in 1965 increased the non-permanent membership from six to ten, bringing the total membership to fifteen. Calls for further reform, particularly by the G4 nations (Brazil, Germany, India, and Japan), seek to expand both permanent and non-permanent seats to better reflect the geopolitical realities of the post-1945 world, but this requires a Charter amendment and ratification by two-thirds of member states, including all P5.