Russian troops flooded the Russian-speaking Ukrainian region of Crimea on Saturday, giving President Vladimir Putin abundant options should he decide to use the new military authority his parliament gave him.
U.S. President Barack Obama spoke with Putin by telephone Saturday after the upper house of Russia's Parliament unanimously voted Saturday to authorize military force in Ukraine. The White House said the U.S. was "suspending" its preparations for the next G-8 summit of industrialized nations — scheduled to be held in Russia.
Moscow already had thousands of military personnel in Crimea, where the Russian Black Sea naval fleet is based, and Ukraine's defense minister claimed Saturday that 6,000 more Russian troops had arrived.
Masked, well-armed men ringed the Interior Ministry and the Parliament buildings in Simferopol, the Crimean capital, after as many as a dozen Russian transport planes flew in men, weapons and ammunition overnight.
The Russian forces appeared to be establishing "legitimate" defensive positions around some of Moscow's military bases in a "self-defense posture only," U.S. officials told NBC News on Saturday.
But Ukraine's acting national leaders reacted aggressively, saying any Russian military action would inevitably lead to war and bring an end to relations with Moscow. They said they had put the country's armed forces on "highest" combat alert.