Ukraine has put its armed forces on full alert and warned Russia that military intervention will lead to war shortly after Vladimir Putin gave the green light for an invasion as the upper house of the Russian parliament unanimously approved his request to send troops into the neighbouring state.
The Guardian: Yatseniuk warns of war as Russian military seizes control in Crimea
Military troops of Russia 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.
