The politics of Ukraine take place in a framework of a semi-presidential republic and of a multi-party system. A Cabinet of Ministers exercises executive power (jointly with the president until 1996). Legislative power is vested in Ukraine’s parliament, the Verkhovna Rada (Ukrainian: Верховна Рада, lit. ’Supreme Council’).

As part of the Soviet Union as the Ukrainian Soviet Socialist Republic until 1991, the political system featured a single-party socialist-republic framework characterized by the superior role of the Communist Party of Ukraine (CPU), the sole-governing party then permitted by the Ukrainian SSR’s constitution. In 1996, the current constitution replaced the previous constitution that was introduced in 1978.

From 2014 changes in the administration on-the-ground in Crimea, Donetsk and Luhansk have complicated the de facto political situation associated with those areas.

Source: Wikipedia