Moscow’s development of nuclear-powered drones has been closely watched in recent years, amid concern that Russia could be adding a “doomsday” weapon capable of unleashing tidal waves to its arsenal.
The Poseidon can target coastal areas with a heavy nuclear weapon, causing a devastating tsunami wave. Putin has said its tests have been successful.
He first mentioned the nuclear-powered drone among an array of other new weapons in a state-of-the-nation address last year, saying they would render U.S. missile defense systems useless.