First Meeting of Security Council with 15 Members, S/PV.1271
When the United Nations was established in 1945, the Security Council was comprised of eleven members: five permanent and six non-permanent members. The five permanent seats were held by the United States, France, United Kingdom, Soviet Union, and China, while the remaining seats were designated as non-permanent and rotated among the other 46 Member States for two-year terms. As new Member States joined the Organisation, they expressed the need for equitable geographic representation in the Council and on 17 December 1963, the General Assembly approved amendments to Articles 23, 27 and 61 of the UN Charter to increase the number of members of the Security Council from eleven to fifteen and to increase from seven to nine the number of votes required for adoption of decisions by the Council. On 20 December 1965, the General Assembly adopted resolution 2101(XX), amending article 109 of the Charter; replacing the number of voting members from “seven” with “nine”.
On 1 February 1966, the Security Council meets for the first time in the history of the United Nations with an expanded membership of 15 and a more equitable representation of all the regions of the world.