"Yanukovych is a carrier of information about the Russian Federation, the actions of the Russian Federation, its plans, attitude, about the world, about Crimea and other things," he said.

"The Russian government will never give Yanukovych to anyone, because he has a very confidential information," Chumak said.

"I'm afraid that Yanukovych could end up like Litvinenko,” Chumak said, referring to fugitive FSB officer Alexander Litvinenko, who died in London in 2006 after being poisoned with radioactive Polonium. The UK authorities have accused Russia of being behind the killing.

“The situation is that we are unlikely to get [Yanukovych] in any form, [alive or dead]," Chumak said.