The Uzbek SSR participated in the referendum in March 1991 as a part of the proposed Union of Soviet Sovereign States. This never came to pass after unsuccessful coup attempt events between 19 and 21 August 1991 in Moscow. In the aftermath, the Uzbek SSR was renamed the Republic of Uzbekistan and declared its independence on 31 August 1991, formally remaining a part of the Soviet Union until 26 December 1991. With the final collapse of the Soviet Union, the Uzbek SSR became the independent nation of Uzbekistan although the 1978 Constitution remained in use. The referendum was confirmed on 29 December 1991.