Ukraine's ousted President Viktor Yanukovych asked Russia to deploy its troops across the border to establish "peace, law and order" and "defend the people of Ukraine," Russia's ambassador to the UN has said.
Faced with calls from almost all UN Security Council members to pull Russian forces out of the Crimea, Ambassador Vitaly Churkin on Monday read out a letter that he said was signed by Yanukovych, whom Moscow considers to be Ukraine's legitimate leader, asking Russian President Vladimir Putin for help.
In the letter, Putin was asked "to use the armed forces of the Russian Federation to restore legitimacy, peace, law and order, stability and to defend the people of Ukraine," as the country was "on the brink of civil war," Itar-Tass reported.
Churkin also showed the council a copy of the letter, which was dated Saturday.
The Ukrainian mission to the United Nations said that Moscow has deployed 16,000 of its troops in Crimea, Fox News reported.
The troops were deployed by "military ships, helicopters, cargo airplanes from the neighboring territory of the Russian Federation," the Ukrainian mission said in a letter.
The mission accused Russian forces of using stun grenades against Ukrainian soldiers and trying to "seize, block and control crucial governmental and military objects of Ukraine in Crimea," including all airports, radio stations, and military and coast guard bases.
U.S. Ambassador Samantha Power called Russia's mobilization "a response to an imaginary threat," ABC News reported.
"What is happening today is a dangerous military intervention in Ukraine. It is an act of aggression. It must stop," she said.
At a meeting of the UN Human Rights Council in Geneva earlier on Monday, Russian Foreign Minister Sergei Lavrov said troops had been deployed to protect Ukraine's massive Russian-speaking population from attacks by ultranationalists, The New York Times reported.
He said Russia needed to keep its troops in Ukraine "until the normalization of the political situation."
UN Secretary General Ban Ki-moon, who on Sunday sent his deputy to Kiev to evaluate and report on the situation, said "it is important that both sides should lower their temperature."