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President Obama is calling Russia's intervention in Ukraine a violation of both international law and Ukrainian sovereignty. 

The President's comments today come as the U.S. weighs possible sanctions against Russia for sending troops into the Crimean region. 

Obama called the action "unprovoked" and said his administration is reviewing a series of possible steps to "isolate Russia." 

He also warned that Russia is on the wrong side of history.

Meantime, the U.S. and Russian ambassadors to the United Nations are sparring over Russia's military intervention in Ukraine. At a UN Security Council meeting, American Ambassador Samantha Power said Russian troop movements into Ukraine's Crimean  region are unjustified.  She called it an act of aggression and a dangerous military escalation. 

Russia's Ambassador said his country is reacting to the transitional Ukrainian government's efforts to root out pro-Moscow supporters and political parties.  Power said there's no evidence to support that assertion. (Metro Networks Inc)