MOSCOW, March 21 (RAPSI) – Russian upper house of parliament, the Federation Council, on Friday approved the federal constitutional bill on accession of Crimea and Sevastopol.

155 senators votes yes unanimously, there were no votes against or abstained.

Russian President Vladimir Putin signed a decree Monday recognizing Crimea as an independent state, following a referendum Sunday that saw voters overwhelmingly support secession from Ukraine and reunification with Russia.

That day the US and EU imposed sanctions on senior Russian officials, including visa bans and asset freezes, in protest of Russian support of Crimea's actions.

Notwithstanding, on Tuesday leaders of the Autonomous Republic of Crime and Putin signed a treaty unifying Crimea with Russia.

Crimea, a largely Russian-speaking republic within Ukraine, was part of Russia until it was gifted to Ukraine by Khrushchev in 1954. Putin said in an official address to federal and regional officials Tuesday that the decision was made with evident violations of the constitutional norms prevailing at the time.

Crimea moved to independence from Ukraine by having refused to recognize as legitimateits new government that came to power following the ouster of President Viktor Yanukovich last month.