(SIMFEROPOL, Ukraine) -- Unidentified gunmen, driving transport trucks and other vehicles with Russian license plates, surrounded a Ukrainian military base on Sunday morning.
Ukraine ordered a full military mobilization of its troops after Russia began to bolster its presence in the Crimea region. New Prime Minister Arseniy Yatsenyuk said on Sunday that Ukraine is "on the brink of disaster."
One Ukrainian deputy commander of a separate base -- which had a standoff of its own with militiamen -- told ABC News that they had been ordered twice to leave the base and give up their weapons. He declined, saying that his orders were to stand firm.
BBC News reports that Ukrainian military personnel are currently receiving orders from the Ukrainian Defense Minister in Kiev, the Russians and the local authority, complicating matters.
Speaking to George Stephanopoulos on This Week, Secretary of State John Kerry said that "all options are on the table." Kerry spoke of the international treaties that Russia has violated by means of its actions in Ukraine, adding that a diplomatic solution is possible if Russia opted to cooperate. Kerry also said that the U.S. was prepared to boycott the G8 summit in Sochi, Russia if necessary, and that Russia risked wasting the $60 billion spent on the Olympic Games if it continues to ignore international law.
On Saturday, the U.S. ceased preparatory discussions for the G8 summit, a move copied by Canada, France and the United Kingdom. On Sunday, Canada announced that it would withdraw its ambassador from Moscow.
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