"It's clear that World War Three can only be a nuclear war," Lavrov said in an online interview with Russian and foreign media.

"I would like to point out that it's in the heads of Western politicians that the idea of a nuclear war is spinning constantly, and not in the heads of Russians," he said.

"Therefore I assure you that we will not allow any provocations to throw us off balance," Lavrov added.

He also compared the United States to French Emperor Napoleon Bonaparte and German dictator Adolf Hitler.

"In their time, both Napoleon and Hitler set themselves the task of subjugating Europe. Now the Americans have subdued it," Lavrov said.

On Sunday, Russian President Vladimir Putin ordered Russia's nuclear forces be put on high alert, accusing the West of taking "unfriendly" steps against his country.

Moscow has the world's largest arsenal of nuclear weapons and a huge cache of ballistic missiles which form the backbone of the country's deterrence forces.

Putin announced the invasion last week in Ukraine to defend separatists in the east of the country, and "demilitarise and de-nazify" its pro-Western neighbour.