Speaking at a press conference on Thursday, the Russian official compared the 1945 atomic bombings of Hiroshima and Nagasaki with "Nazi crimes," and called them "crimes against humanity."

"I think that we should discuss this topic together with lawyers and international law experts because crimes against humanity have no limitation period," he was quoted as saying by the Itar-Tass news service.

"As we well know, the bombings of the two peaceful Japanese cities could not be explained from a military point of view," he said. "The atomic bombings... were solely an intimidation demonstration resulting in the deaths of hundreds of thousands of peaceful residents."

"This really runs the risk that what is increasingly a Cold War situation between the United States and Russia could turn into a hot war," he said.