North Korea has revealed for the first time that it is constructing a nuclear-powered submarine, a development that could significantly threaten South Korea and the U.S.
On Saturday, state media released images of what it described as a “nuclear-powered strategic guided missile submarine,” highlighting leader Kim Jong Un’s visits to major shipyards involved in warship production. While the Korean Central News Agency (KCNA) did not provide specific details about the vessel, it confirmed that Kim was briefed on its construction.
According to Moon Keun-sik, a submarine expert from Seoul’s Hanyang University, the submarine is likely a 6,000 to 7,000-ton-class vessel capable of carrying around 10 missiles. He noted that the mention of “strategic guided missiles” suggests the submarine would be armed with nuclear-capable weapons. “This poses a serious threat to both South Korea and the U.S.,” Moon stated.
Developing a nuclear-powered submarine has been one of Kim’s key military goals since a major political conference in 2021, where he outlined plans to enhance North Korea’s weaponry in response to what he called increasing U.S.-led military threats. Other ambitions included solid-fueled intercontinental ballistic missiles, hypersonic weapons, spy satellites, and multi-warhead missiles, with North Korea conducting several tests since then.
The ability to launch missiles from underwater adds a strategic advantage, as such launches are harder for adversaries to detect in advance. However, questions remain about how North Korea, an economically strained and heavily sanctioned nation, has acquired the resources and technology for such an advanced vessel.
Moon speculated that North Korea might have received Russian technological assistance in exchange for supplying conventional weapons or troops to aid Russia’s war in Ukraine. He estimated that the submarine could be launched within one or two years for testing before entering active service.
North Korea currently operates an estimated 70-90 diesel-powered submarines, forming one of the world’s largest fleets. However, most of these submarines are aging and can only deploy torpedoes and mines rather than missiles. In 2023, North Korea claimed to have launched its first “tactical nuclear attack submarine,” but foreign analysts doubted the claim, believing it was likely a modified diesel-powered vessel first revealed in 2019. There has been no confirmation of its deployment.
Since 2016, North Korea has conducted multiple underwater ballistic missile tests, but all were launched from a single 2,000-ton-class submarine equipped with just one launch tube. Many experts believe this submarine serves as a test platform rather than an operational military asset.
In the days leading up to joint U.S.-South Korea military exercises set to begin on Monday, North Korea has intensified its aggressive rhetoric. During his visits to the shipyards, Kim emphasized the simultaneous modernization of surface and underwater warships. He also stressed the importance of creating “overwhelming” warships capable of countering what he called the “gunboat diplomacy” of hostile nations, according to KCNA.
