Vladimir Putin Has said, Russia is developing new nuclear weapons that are immune to enemy interception.
The Russian President said this includes a nuclear-powered cruise missile and an underwater drone.
Speaking in a state-of-the-nation speech, Mr Putin claimed the high-speed cruise missile, which was tested late last year, has an unlimited range and can penetrate any missile defence.
The high-speed underwater drone can carry a nuclear warhead and target both aircraft carriers and coastal facilities, the president also claimed.
A new heavy intercontinental ballistic missile (ICBM) called Sarmat is also under testing and has a range and number of warheads exceeding the capabilities of its predecessor, Mr Putin added.