
Russia has launched its latest nuclear-armed submarine under the watchful eye of President Vladimir Putin.

The sub, named Belgorod, was launched from the Sevmash plant in northwestern Russian on Tuesday while Putin observed via teleconference.

Belgorod is designed to carry nuclear-armed Poseidon drones, a doomsday weapon that Russia says will be capable of destroying entire cities by triggering a tsunami.

Russia launched its newest submarine - the world's longest, named Belgorod - on Tuesday under the watchful eye of President Putin, who observed via teleconference

The Belgorod, whose construction will be finished at sea, is designed to carry Moscow's latest super weapon - nuclear-armed drones named Poseidon which Russia claims are capable of causing tsunamis

Mikhail Budnichenko, director of the shipyard, said during the launch ceremony that 'the enterprise's shipbuilders will fulfill all the tasks of building ships within the established timeframe and with high quality.'

The submarine will be finished while afloat and TASS quoted a defense source saying the nuclear reactor will be tested later this year, with sea trials set for 2020 and deployment by the end of that year.

Putin 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.

The drones are built in a similar shape as torpedoes but are much larger than the conventional weapons - measuring up to 79ft long - which is why they need to be carried by specially designed submarines.

Once launched, the weapon can be controlled remotely to bypass defences and has a theoretically unlimited range thanks to its nuclear reactor engine.

Reports on its speed have varied, putting it as low as 70mph and as high as 124mph, making it very difficult to stop.

While specifications of Poseidon are hazy, Russia has released this footage which it claims shows the drone, and the Pentagon has said it believes the weapons are real

Putin is taking a heavy interest in the Poseidon project and the crew of the Belgorod will report directly to him, rather than Navy commanders, effectively making it an underwater secret service base

The weapons could also act as unmanned underwater vehicles (UUVs), capable of operating miles below the waves to map the ocean floor using a sonar imaging system known as side-scanning.

However, the UUVs could also be deployed to sabotage undersea power and internet cables during conflict.

The giant sub also has a 180ft mini-submarine docked underneath it. The 25-man craft can be used for research, rescue and special military operations.

In what is regarded as a sinister development, the submarine's commanders will report directly to President Putin rather than to the country's naval top brass, making Belgorod more like a deep-sea intelligence agency than a conventional submarine.

The Belgorod is expected to operate in the Arctic and the North Atlantic – areas where Russian submarine activity has increased tenfold in recent years. There has also be a huge rise in Russian approaches to UK territorial waters.

In 2010, the Royal Navy had to respond to only one intrusion, but in 2017, 33 separate incidents required a response by British ships or submarines.

The Navy is developing its own fleet of UUVs, but they are not expected to enter service for another eight years, according to sources.