President Vladimir Putin has formally notified the government and the parliament of Crimea's request to join Russia hours before he is to speak on the topic.
The Black Sea peninsula on Sunday voted overwhelmingly to secede from Ukraine and seek annexation by Russia.
Putin on Tuesday morning notified the government and both chambers of the Russian parliament of Crimea's request ahead of his afternoon speech in which he is expected to voice his opinion on the peninsula's bid.
The president signed a decree recognizing Crimea as a "sovereign and independent country" hours after the US and the European Union slapped senior Russian officials with sanctions for Russia's intervention into Ukraine.
Russian troops have been occupying the peninsula for more than two weeks now.