Russia has prepared amendments to its nuclear doctrine and they will now be formalised, Kremlin spokesman Dmitry Peskov said in an interview to state TV reporter Pavel Zarubin on Sunday.
President Vladimir Putin warned the West on Wednesday that under proposed changes to the doctrine - which sets out the circumstances in which Moscow could use nuclear weapons - Russia could use nuclear arms if it was struck with conventional missiles.
He also said that Moscow, under the proposed changes, would consider any assault on it supported by a nuclear power to be a joint attack.