Crimea's prime minister says preliminary results from Sunday's referendum on whether to break away from Ukraine indicate that 93 percent voted for their region to join Russia.
Less than one hour after the polls closed, the White House released a statement saying it rejects Sunday's referendum. It said the international community will not recognize the results of a poll administered under threats of violence and intimidation from a Russian military intervention that violates international law.
The statement added that no decision should be made about the future of Ukraine without the Ukrainian national government. It said the presidential elections planned for May 25 will provide a legitimate opportunity for all Ukrainians to make their voices heard on the future of their country.
Voter turnout in Crimea, a peninsula on the Black Sea, was estimated at about 64 percent Sunday.
The United States, the European Union, and the European Council all released statements Sunday calling the referendum illegal and illegitimate, and warning its outcome will not be recognized internationally.
Secretary of State John Kerry and Russian foreign minister Sergei Lavrov on Sunday agreed to push for Ukrainian constitutional reforms for power sharing and decentralization as a solution to its political crisis.
During a phone call Sunday, Kerry also told Lavrov the United States will not recognize the referendum.
Reuters news service reports Ukrainian Prime Minister Arseny Yatsenyuk is vowing to track down those promoting separatism in Crimea. He said Ukraine will find all ringleaders of separatism who are trying to destroy Ukrainian independence.
Also in Kyiv, Ukraine's acting defense minister told reporters the defense ministries of Ukraine and Russia have agreed on a truce in Crimea until March 21.
Defense Minister Ihor Tenyukh said an agreement has been reached with Russia's Black Sea fleet, which is stationed in Crimea, that no measure will be taken against Ukrainian military facilities during the truce. He said Urkaine's military sites are now replenishing their supplies.
During a phone call with Russian President Vladimir Putin, German Chancellor Angela Merkel proposed an Organization for Security and Cooperation in Europe mission in Ukraine be expanded immediately.
Crimea is a primarily ethnic-Russian majority region of Ukraine. Moscow says it has the right to protect its interests in Crimea.