Byelorussian Soviet Socialist Republic
However, the Byelorussian Soviet Socialist Republic and the Ukrainian Soviet Socialist Republic had already joined the UN as original members on October 24, 1945, together with the Soviet Union. After declaring independence, the Ukrainian Soviet Socialist Republic changed its name to Ukraine on August 24, 1991 and on September 19, 1991, the Byelorussian Soviet Socialist Republic informed the UN that it had changed its name to the Republic of Belarus.