Poseidon is a nuclear-powered and nuclear-armed unmanned underwater vehicle under development by the Russian Federation that can deliver conventional and nuclear payloads. According to Russian state TV, it may be able to deliver a thermonuclear cobalt bomb of up to 100 megatonnes against enemy's naval ports and coastal cities. In 2018, the U.S. Nuclear Posture Review stated that Russia is developing a "new intercontinental, nuclear armed, nuclear-powered, undersea autonomous torpedo".