North Korea has revealed for the first time a nuclear-powered submarine currently under construction, a potential security threat to both South Korea and the U.S. State media released images on Saturday showing what was described as a “nuclear-powered strategic guided missile submarine,” accompanied by reports of leader Kim Jong Un’s visits to key shipyards where warships are produced.
The Korean Central News Agency (KCNA) did not provide specific details about the submarine but mentioned that Kim Jong Un was briefed on its construction. According to Moon Keun-sik, a South Korean submarine expert at Seoul’s Hanyang University, the naval vessel appears to be in the 6,000-ton to 7,000-ton class and capable of carrying about 10 missiles. He noted that the term “strategic guided missiles” suggests the submarine could carry nuclear-capable weapons. Moon stated, “It would be a significant threat to both us and the U.S.”
A nuclear-powered submarine was part of a broad list of advanced weapons that Kim Jong Un pledged to develop during a significant political conference in 2021, citing the need to counter what he described as increasing U.S.-led military threats. Other weapons on the list included solid-fueled intercontinental ballistic missiles, hypersonic weapons, spy satellites, and multi-warhead missiles. Since then, North Korea has conducted a series of tests to acquire these capabilities.
North Korea’s increasing capability to launch missiles from underwater raises concerns, as it makes it harder for its adversaries to detect such launches in advance. There have been questions about how North Korea, a country facing heavy sanctions and economic challenges, could acquire the resources and technology to build nuclear-powered submarines.
Moon, the submarine expert, suggested that North Korea might have received technological assistance from Russia to develop a nuclear reactor for the submarine, possibly in exchange for providing conventional weapons and troops to support Russia’s war in Ukraine. He also mentioned that North Korea could test the submarine’s capabilities within the next one or two years before it is officially deployed.
North Korea is believed to possess 70-90 diesel-powered submarines, making it one of the largest fleets in the world. However, most of these submarines are aging and can only launch torpedoes and mines, not missiles. In 2023, North Korea claimed to have launched its first “tactical nuclear attack submarine,” but foreign experts raised doubts about this announcement. They speculated that the vessel was likely a diesel-powered submarine revealed in 2019, and Moon stated that there has been no confirmation of its deployment.
Since 2016, North Korea has carried out multiple underwater-launched ballistic missile tests, all from a 2,000-ton-class submarine with a single launch tube. Many experts consider this vessel more of a test platform rather than an operational submarine.
Recently, North Korea has ramped up its fiery rhetoric against the U.S. and South Korea in anticipation of their upcoming annual military drills, scheduled to begin Monday. During his visits to shipyards, Kim Jong Un emphasized North Korea’s goal of modernizing both surface and underwater warships at the same time. He stressed the importance of ensuring these “incomparably overwhelming warships” fulfill their mission to counter “the inveterate gunboat diplomacy of hostile forces,” according to state media.