An overwhelming 95.5 percent of Crimeans voted Sunday to become part of Russia in a referendum deemed "illegal" by US and UK

An overwhelming 95.5 percent of Crimeans voted Sunday to become part of Russia in a referendum deemed "illegal" by US and UK.

With 50 percent of ballots counted, referendum commission chairman Mykhaylo Malyshev said 3.5 percent had voted to remain in Ukraine with wider autonomous powers and 1.0 percent were "spoiled ballots."

Crimea's leader Sergiy Aksyonov said the referendum "will go down in history."

"Today we took a very important decision that will go down in history," Aksyonov tweeted in the wake of the exit poll. He said Crimea's regional government will make a formal application Monday to join the Russian Federation.

"The Supreme Soviet of Crimea will make an official application for the republic to join the Russian Federation at a meeting on March 17," Aksyonov said in a tweet.

Outraged US President Barack Obama hinted at possible additional sanctions on Russia, warning his Russian counterpart Vladimir Putin that the United States and its allies would "never" recognize Crimea's breakaway vote Sunday.
  
In a telephone call, Obama told Putin that the vote violated the Ukrainian constitution. "President Obama emphasized that the Crimean 'referendum,' which violates the Ukrainian constitution and occurred under duress of Russian military intervention, would never be recognized by the United States and the international community," the White House said in a statement.

The Kremlin said earlier that the call was initiated by the American side, as relations between Russia and the United States plunged to their lowest point since the Cold War.
  
Putin told Obama that the referendum was fully legal, "in line with the norms of international law and the UN charter."

For its part, Britain slammed the vote as a "mockery" of democracy and refused to recognize the referendum's outcome.

Speaking in Brussels ahead of a meeting of European Union foreign ministers on Monday, Foreign Secretary William Hague condemned the vote as being in ‘breach’ of the Ukrainian constitution.