US warns Russia of 'costs' over 'armed invasion' of Crimea

Russia has been reportedly accused by Ukraine of an "armed invasion", after the country deployed troops to Crimea, invoking strong criticism from the White House.

US President Barack Obama said that the United States would stand with the international community in affirming that there will be costs for any military intervention in Ukraine.

According to the Fox News, Obama said that the U.S. government was deeply concerned by reports of Russian military movements and warned any violation of Ukraine's sovereignty would be deeply destabilizing.

Meanwhile, it is reported that Russian aircraft carrying nearly 2,000 suspected troops have landed at a military air base close to the regional capital of the Crimean peninsula.

Sergiy Kunitsyn, the Ukrainian president's special representative in Crimea said that thirteen Russian aircraft landed at the airport of Gvardeyskoye (near Simferopol) with 150 people in each one.

Warning against the dangers of "irresponsible Western policy", ousted Ukrainian President Viktor Yanukovych said that while he trusted the decency of Western mediators when he signed a peace deal last week, the recent actions by the opposition ran counter to the agreement.