Belgorod, set to be the largest submarine in the world, was first reported in 2017. It was initially expected to be used on research missions, however, it has now been claimed that it will have six deep-sea nuclear warheads attached. Named “Poseidon”, the 70ft underwater drones are reportedly powered by a small nuclear reactor and can function at a depth of 1,000 metres. Related articles Russian fighter jets practice air-to-air missile strikes as Putin s... NUCLEAR FEARS: Russia accuses US of hiding nuclear weapons Last week, Defence Minister Sergey Shoigu said the plan is to deploy the submarine from Severodvinsk yard, in northern Russia, before summer 2019. This will then reportedly be followed by a year of testing, before Belgorod enters active duty in 2020. Mr Shoigu told Russian daily newspaper Kommersant: “The whole complex of works should be completed this year. “These ships will determine the future appearance of our submarine fleet. The Belgorod will now carry Poseidon drones (Image: GETTY/SG) The Poseidon drone being loaded onto the submarine (Image: H I SUTTON) They will increase the defence potential and strengthen Russia's position in the oceans Defence Minister Sergey Shoigu “They will increase the defence potential and strengthen Russia's position in the oceans.” Meanwhile, another submarine, the “Khabarovsk”, is under construction at the same yard and is expected to be put to water in 2020, ready for missions two years later. Video footage was shared last month showing a test-launch of a Poseidon drone, which the Khabarovsk is also expected to carry. It is unclear whether the test took place in the ocean or within a simulation. The Poseidon rocket is capable of being fired 1,000m below the water (Image: YOUTUBE) Russian plans were shared on state tv last year (Image: BBC) It is likely Russian President Vladimir Putin will present in Severodvink when Belgorod is put in water. Asked about Russia’s new nuclear-powered drones, Norway’s Foreign Minister Ine Eriksen Soreide revealed his concerns. He told the Barents Observer: “It is worrying that countries are developing new nuclear capabilities.” The existence of the weapon was first officially announced by Putin in his annual state-of-the-nation speech in March 2018. All rights reserved for this news site express.co.uk and under his responsibility