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President Barack Obama spoke on the situation in Ukraine on Friday, saying "we are now deeply concerned" about recent events.

Obama said any military movements taken by Russia inside of Ukraine would be "deeply destabilizing."

"The Ukrainian people deserve the opportunity to determine their own future," Obama said.

Obama said the United States will stand with the international community, warning Russia "there will be costs" for any military intervention in Ukraine.

Below, more from the AP:

WASHINGTON (AP) — U.S. officials said Friday that President Barack Obama may scrap plans to attend an international summit in Russia this summer and could also halt discussions on deepening trade ties with Moscow, raising specific possible consequences if Russia should intervene in Ukraine. Obama himself bluntly warned of unspecified "costs" for Russia.

"Any violation of Ukraine's sovereignty and territorial integrity would be deeply destabilizing," Obama declared. Such action by Russia would represent a "profound interference" in matters that must be decided by the Ukrainian people, he said.

While the president spoke only of "reports" of military movements inside Ukraine, the officials said the U.S does believe that Russia is intervening. more