Will Putin go nuclear?

Available for over a year

President Putin says military reservists are to be sent to Ukraine as part of a partial mobilisation of Russian forces. In a televised address to the nation, he said this was a necessary step to ensure Russian territorial integrity. He accused the West of wanting to see Russia weakened and said a threat to retaliate further was "not a bluff". The EU and Nato said his rhetoric on nuclear weapons was dangerous. So what are the weapons President Putin is talking about? How powerful are they? And should we be worried? The BBC's Security Correspondent, Gordon Corera has the answers. Image Credit: Ghetty images