Russian President Vladimir Putin's decree recognising Crimea as a "sovereign and independent country" has triggered the toughest Western sanctions against Russia since the Cold War.
But one of the top Russian officials hit by sanctions mocked US President Barack Obama.
"Comrade Obama, what should those who have neither accounts nor property abroad do? Have you not thought about it?" Deputy Prime Minister Dmitry Rogozin tweeted. "I think the decree of the President of the United States was written by some joker."
Moscow considers the vote legitimate and Mr Putin plans to address both houses of parliament tomorrow on the Crimean situation.
Putin's decree recognising Crimea as a 'sovereign country' has triggered the toughest sanctions against Russia since the Cold War.
With over half of the votes counted, over 95% of people in Crimea have voted to become part of Russia, election officials have said.
At some point the West's warnings will have to become deeds, part of the problem is they don't know which Putin they're dealing with.