The Ukraine was one of the founding members of the United Nations when it joined in 1945 as the Ukrainian Soviet Socialist Republic along with the Byelorussian Soviet Socialist Republic signed the United Nations Charter when they were part of the Soviet Union . Ukrainian Soviet Socialist Republic . The Ukrainian SSR was a founding member of the United Nations , although it was legally represented by the All-Union state in its affairs with countries outside of the Soviet Union . Upon the Soviet Union 's dissolution and perestroika , the Ukrainian SSR was transformed into the modern nation-state and renamed itself to Ukraine , although Ukraine 's new constitution was only ratified on 28 June 1996 .
The Ukrainian Soviet Socialist Republic became Ukraine before the founding of the United Nations.