Russia and the West locked horns over the escalating crisis in Ukraine at UN security council emergency talks Sunday as deadly clashes flared between Ukrainian forces and pro-Kremlin militias.
Russia blamed the rising tensions on the pro-Western interim government in Kiev, which took power in February, while Britain, France and the United States pointed the finger at the Kremlin.
The emergency session was the 10th round of UN security council talks on the crisis and comes after Kiev threatened to launch a military operation unless pro-Russian forces stand down.
The General Assembly last month passed a resolution condemning Russia's annexation of Crimea but analysts say the UN talks will achieve little more than posturing on all sides.
Russia, which called the meeting, said it was "the West who will determine the opportunity to stop the civil war in Ukraine."
"There has already been bloodshed and a further escalation must be swiftly stopped," ambassador Vitaly Churkin told the council.
"The international community must ask Kiev to stop and implement all its commitments.
"Kiev should stop the use of force against eastern Ukrainian people and start a genuine dialogue," Churkin said.
US ambassador Samantha Power accused Russia of waging propaganda and bombarding Ukraine with incitement and violence.
"This is the saddest kind of instability. It is completely man made. It was written and choreographed in and by Russia," Power told the 15-member council.
The attacks were especially unsettling for both Kiev and Western leaders because of their similarity to events leading up to Russia's annexation of Ukraine's Crimean Peninsula.
Power urged Russia to explain why 40,000 of its forces are massed on the Ukrainian border and find constructive ideas to stop armed attacks on government buildings in eastern Ukraine.
British ambassador Mark Lyall Grant described the last 48 hours in eastern Ukraine as a "dangerous escalation of an already dangerous situation."
"Russia is seeking to impose its will on the people of Ukraine using misinformation, intimidation and aggression," he said, branding Moscow's behavior "completely unacceptable."
He urged Russia to redeploy its troops away from the border and "cease all activity designed to heighten tensions and sow discord."
UN Assistant Secretary-General for Political Affairs Oscar Fernandez Taranco said at least one Ukrainian officer had been killed in a gun battle and numerous other people had been reported injured during skirmishes in eastern Ukraine.
During the last 24 hours, he said, at least five new cities in the region had been targeted by uprisings and seizures of government buildings.
"The situation is therefore now more combustible than ever," Fernandez Taranco said, warning against a spillover of "potentially severe consequences."
Ukraine's acting president Oleksandr Turchynov declared the launch of a "full-scale anti-terrorist operation" a day after masked gunmen stormed police and security service buildings.
The Russian foreign ministry accused Ukraine's leaders of "waging war against their own people" and demanded that the UN Security Council immediately address Kiev's use of force.