Tension dramatically mounted in Ukraine's Crimea region Friday as its ambassador to the United Nations warned Russia against any further violation of its territorial borders, a warning that came as the United States urged Russia to pull back from the region or face possible consequences. "We are now deeply concerned by reports of military movements taken by the Russian Federation inside Ukraine," U.S. President Barack Obama said in televised comments from the White House. "...It would be a clear violation of Russia's commitment to respect the independence and sovereignty and borders of Ukraine and of international laws." Obama said any violation of Ukraine's sovereignty and territorial integrity would be "deeply destabilizing, and he warned "the United States will stand with the international community in affirming that there will be costs for any military intervention in Ukraine."
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U.S. State Department warns Americans against non-essential travel to Ukraine
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"There will be costs for any military intervention in Ukraine," President Barack Obama says
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"We are strong enough to defend ourselves," Ukrainian ambassador says
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Russian President Vladimir Putin to EU leaders: Ukraine must avoid an escalation of violence
And Ukraine suspects Russia of fomenting tension in the autonomous region that might escalate into a bid for separation by its @placeholder majority.