North Korea reveals nuclear-powered submarine

North Korea has for the first time announced that a nuclear-powered submarine is under construction, a weapons system that could pose a major security threat to South Korea and the United States, CNN reported.

North Korean state media on March 8 released photos showing what they called a "nuclear-powered strategic guided missile submarine" when reporting on leader Kim Jong-un's visit to major shipyards where warships are built.

The Korean Central News Agency (KCNA) did not provide details about the submarine, but said leader Kim had been briefed on its construction.

Moon Keun-sik, a South Korean submarine expert who teaches at Hanyang University in Seoul, said the naval vessel appeared to be a 6,000-ton or 7,000-ton vessel that could carry about 10 missiles. He said the use of the term "strategic guided missile" meant it would carry nuclear-capable weapons. "That would definitely threaten South Korea and the United States," Moon said.

A nuclear-powered submarine was among a long list of cutting-edge weapons that leader Kim Jong-un mentioned at a major political conference in 2021 as part of his strategy to counter escalating US-led military threats. Other weapons include solid-fuel intercontinental ballistic missiles, hypersonic weapons, spy satellites and multiple-warhead missiles. North Korea has since carried out a series of tests to acquire them.

North Korea's ability to launch missiles from underwater is a worrying development, as such launches are unlikely to be detected by its adversaries.

Questions have arisen about how North Korea, a country heavily sanctioned by the United States, could have acquired the resources and technology to build nuclear-powered submarines.

Moon, a submarine expert, said North Korea may have received Russian technological assistance to build a nuclear reactor for use in a submarine in exchange for conventional weapons and troops to support Russia's war effort against Ukraine. He also said North Korea could launch the submarine in one or two years to test its capabilities before actual deployment.

North Korea is estimated to have between 70 and 90 diesel-powered submarines in one of the world's largest fleets, but they are mostly old vessels capable of launching torpedoes and mines, not missiles, according to CNN.

In 2023, North Korea said it had launched its first strategic nuclear attack submarine, but foreign experts doubted North Korea's announcement and speculated that it was likely a diesel-powered submarine unveiled in 2019.

North Korea has conducted a series of underwater ballistic missile tests since 2016, but all of the launches have been from the same 2,000-ton submarine with a single launch tube.

Many experts call this a test platform rather than an active submarine.

In recent days, North Korea has harshly criticized the United States and South Korea as the two countries hold annual military exercises, scheduled to begin on March 10.

During a visit to shipyards, leader Kim Jong-un said North Korea aims to modernize both surface and underwater warships. He stressed the need to "make the overwhelmingly powerful warships complete their tasks" to curb "the deep-rooted gunboat diplomacy of the hostile forces," KCNA reported.