NATO Chief Andres Fogh Rasmussen stressed that Russia would be making an "historic mistake" if it was to intervene in Ukraine any further.

NATO Chief Andres Fogh Rasmussen stressed that Russia would be making an "historic mistake" if it was to intervene in Ukraine any further.

"It would have grave consequences for our relationship with Russia and it would further isolate Russia internationally," said the Western military alliance leader.

"I urge Russia to step back and not escalate the situation in east Ukraine," he said at a Paris seminar.

"If Russia were to intervene further in Ukraine it would be a historic mistake. It would have grave consequences for our relationship with Russia and it would further isolate Russia internationally."

Earlier on Tuesday, Moscow warned Kiev that any use of force in Ukraine's east could tip the country into civil war.

"We call for the immediate cessation of any military preparations, which are fraught with the risk of unleashing civil war," the Russian foreign ministry said in a statement.
On Monday, a group of Pro-Russian Protests activists in the eastern Ukrainian city of Donetsk have declared their region independent from Kiev.

Last month, Ukraine’s Crimea region rejoined Russia after residents in the peninsula voted in a referendum to break away from Ukraine.

Tensions erupted between Washington and Moscow following bloody protests in Ukraine that led to the ouster of former Ukrainian president Viktor Yanukovych. Russia called the ouster of Yanukovych a Western-backed coup and annexed the strategic region of Crimea, a move that angered both NATO member countries and the United States.