President Obama warned Vladimir Putin of "additional costs" for Russia after a weekend referendum to separate Crimea from the Ukraine went forward.
In a phone call between the leaders on Sunday, Obama told the Russian president that the U.S. and its allies were "prepared to impose additional costs on Russia for its actions."
And the U.S. signaled it could act as soon as Monday to impose sanctions against Russia for its incursion into Crimea, and for conducting the referendum while occupying troops were in place. The referendum to break Crimea away from Ukraine and make it a part of Russia reportedly passed overwhelmingly although the U.S. and other Western nations have rejected the legitimacy of the vote.
"President Obama reiterated that a diplomatic resolution cannot be achieved while Russian military forces continue their incursions into Ukrainian territory and that the large-scale Russian military exercises on Ukraine’s borders only exacerbate the tension," the White House further said of Obama's conversation with Putin.
Obama was defiant about the Crimean vote, saying the vote would "would never be recognized" by the United States and its allies as a legitimate way of determining the political status of the Ukrainian region.
White House press secretary Jay Carney called the referendum, against which Obama had previously warned, "dangerous and destabilizing" for the Ukraine and much of region. Another top aide to Obama further said observers could "expect sanctions designations in the coming days" during an appearance earlier on Sunday on NBC's "Meet the Press."
Obama has phoned his Russian counterpart several times throughout the crisis in Ukraine, none of the calls prompting either leader to yield much to the other's position.