The US President Barack Obama on Monday asserted that US won't tolerate violation of its sovereignty and territorial integrity.
"We cannot stand by when sovereignty and territorial integrity of a nation is flagrantly violated," Obama said at the 70th session of the United Nations General Assembly.
"Ukrainian people are more interested than ever in aligning with Europe instead of Russia," he added.
Relations between the US and Russia have plummeted to new lows amid tension after Russia annexed portions of Ukraine. The growing Russian military presence near the Syrian port city of Latakia has also been a matter of concern for several nations.