North Korea reveals new images of its first ‘nuclear-powered’ submarine

According to Rokna, citing CNN, the images, released by state media, showed leader Kim Jong Un inspecting the guided-missile submarine at an indoor construction site, suggesting the vessel has yet to be launched. Developing a nuclear-powered submarine has been a longstanding goal for Kim, first mentioned at a ruling party congress in 2021. The recent approval by the Trump administration for South Korea to pursue its own nuclear-powered submarines seems to have accelerated Kim’s plans.

Nuclear submarines offer numerous advantages. They can remain submerged for extended periods—potentially years if adequately provisioned—while conventional subs need to surface to run diesel engines and recharge batteries. Nuclear subs are also generally faster and quieter. Currently, only the United States, Russia, China, France, the United Kingdom, and India operate this technology.

Thursday’s images show considerable progress on the vessel, first announced in March. State media reported that the submarine has a displacement of 8,700 tons, putting it on par with most Virginia-class nuclear attack subs in the U.S. Navy. Kim emphasized the submarine’s significance to North Korea’s defense strategy, calling it “literally… based on the strongest offensive power,” according to Korean Central News Agency (KCNA).

Kim criticized South Korea’s nuclear submarine program as a threat to North Korean security, describing it as an action that must be countered. Experts, however, argue that Pyongyang itself bears responsibility for escalating tensions on the Korean Peninsula. Leif-Eric Easley, professor of international studies at Ewha Womans University in Seoul, noted that while Kim is right that nuclear-powered subs may increase instability, North Korea’s own actions have fueled the arms race, threatening neighbors and diverting resources from economic development.

Under a five-year military expansion plan unveiled in 2021, Kim has overseen the development of ballistic missiles capable of reaching the U.S., hypersonic glide vehicles, and two guided-missile destroyers. The second destroyer made headlines this year after capsizing during launch, but it has since been refloated and repaired. Kim described the construction of the submarines and destroyers as “a leap forward in bolstering the combat capabilities of our fleets,” according to KCNA.

Despite these advancements, North Korea’s fleet remains less capable than South Korea’s, which boasts some of the world’s most advanced guided-missile destroyers and new conventional submarines. Easley suggested that Kim may realize his miscalculation once he observes South Korea’s superior technology.

North Korea’s advantage may lie in its earlier access to nuclear-powered submarines. South Korea had long sought such vessels, but a decades-old nuclear agreement with the U.S. prevented construction until October, when President Trump appeared to remove obstacles. However, designing and building these submarines could take up to a decade.

Hong Min, a senior research fellow at the Korea Institute for National Unification in Seoul, told CNN that North Korea could begin missile tests from the submarine within the next two years. Based on the released images, Hong assessed that the sub may already contain a nuclear reactor, leaving only a few stages before launch readiness.

The images also revealed a glimpse of North Korea’s future leadership, as Kim was accompanied by his daughter, believed to be Kim Ju Ae, who has recently appeared publicly multiple times, sparking speculation that he is preparing a successor.