Ukraine's Prime Minister Arseniy Yatsenyuk warned Sunday his crisis-hit country was on the "brink of disaster", accusing Russia of declaring war in a bleak appeal to the international community.
"This is the red alert, this is not a threat, this is actually a declaration of war to my country," he told reporters in English, a day after Russia's parliament approved the deployment of troops to Ukraine.
"If President Putin wants to be the president who started a war between two neighbouring and friendly countries, between Ukraine and Russia, he has reached his target within a few inches. We are on the brink of the disaster."
US leader Barack Obama has branded Russia's parliament vote a "violation of Ukrainian sovereignty" and told his Russian counterpart Vladimir Putin in a phone call that Moscow's reported deployment of troops outside bases that it leases from Ukraine in the Crimea peninsula had broken international law.
Yatsenyuk on Sunday appealed to the international community.
"We believe that our Western partners and the entire global community will support the territorial integrity and unity of Ukraine and will do everything they can in order to stop the military conflict provoked by the Russian Federation," he said.