Putin ready to invade Ukraine, troops seize Crimea
Russian President Vladimir Putin demanded and won his parliament's approval on Saturday to invade Ukraine, where his troops have apparently already seized the Crimea peninsula, spurning Western pleas for restraint.
Talk of confrontation or outright war spread rapidly across Ukraine, with pro-Moscow demonstrators raising the Russian flag above government buildings in several cities and anti-Russian politicians calling for mobilization.
Ukraine's Prime Minister Arseniy Yatseniuk said Russian military intervention would lead to war and any relations with Moscow. He called for a political solution.
Putin's open assertion of the right to deploy troops in a country of 46 million people on the ramparts of central Europe creates the biggest confrontation between Russia and the West since the Cold War.
It also rebuffs Western leaders who had repeatedly urged Russia not to intervene, including U.S. President Barack Obama, who just a day before had held a televised address to warn Moscow of "costs" if it acted.
Troops with no uniform insignia but clearly Russian - some in vehicles with Russian number plates - have already seized Crimea, an isolated peninsula in the Black Sea where Moscow has a large military presence in the headquarters of its Black Sea Fleet. Kiev's new authorities have been powerless to intervene.
Western capitals scrambled for a response, but so far this has been limited to angry words from Washington and its European allies. A U.S. official said Defense Secretary Chuck Hagel had spoken to his Russian counterpart Sergei Shoigu. The official said there had been no change in U.S. military posture.
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Ukraine orders full military mobilisation over Russia moves
Ukraine has ordered a full military mobilisation in response to Russia's build-up of its forces in Crimea.
Acting President Olexander Turchynov has ordered the closure of airspace to all non-civilian aircraft.
US President Barack Obama has called Russian troop deployments a "violation of Ukrainian sovereignty".
Ukraine has said it will seek the help of US and UK leaders in guaranteeing its security. Nato has called emergency talks to be held at 1200 GMT.
Several other measures were announced by Andriy Parubiy, chair of the national security and defence council of Ukraine:
The armed forces would be put on "full combat readiness".
Reserves to be mobilised and trained
Emergency headquarters to be set up
Increased security at key sites, including nuclear plants.
The BBC has seen what appear to be Russian troops digging trenches on the Crimean border.
Heavily armed groups continue to occupy key sites on the peninsula, including airports and communications hubs, although there has been no actual violence.
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Getting ready to bring back Soviet Union? My small country will be snatched right away if they want. 
