North Korea unveils first nuclear-powered ballistic missile Submarine, marking major naval leap
New Delhi, January 23. North Korea has revealed what it claims is its first dedicated nuclear-powered ballistic missile submarine (SSBN), signalling a significant advance in the country’s naval and nuclear capabilities. The vessel was unveiled through state media footage in December 2025 showing leader Kim Jong-un inspecting a submarine construction facility.
If confirmed, the new submarine would represent a major technological leap for the Korean People’s Navy (KPN), whose existing and past submarines have all relied on conventional propulsion. The newly revealed platform is believed to be the largest submarine ever operated by North Korea, with an estimated displacement exceeding 8,000 tonnes. The added size and weight are likely attributed to a nuclear power plant and the integration of what Pyongyang has described as “strategic missiles”, suggesting the capability to deploy nuclear-armed submarine-launched ballistic missiles (SLBMs).
According to assessments, the submarine could carry up to 10 SLBMs in a sail-mounted configuration – an unconventional design not seen on operational SSBNs elsewhere. The platform is also thought to be equipped with six forward-mounted torpedo tubes, likely of 533-mm calibre, along with a chin-mounted sonar array.
While North Korea has not disclosed details of the missile systems to be deployed, analysts believe the submarine is likely to carry a variant of the Pukguksong series of SLBMs, potentially the Pukguksong-5. The missile, last tested in 2021, is considered the most advanced in North Korea’s SLBM programme and is believed to have a range of several thousand kilometres.
The unveiling comes amid a broader effort to modernise the North Korean Navy, much of which still consists of ageing Soviet-era surface vessels and submarines dating back to the early and mid-Cold War period. As part of this push, the KPN inducted two Choe Hyon-class guided missile destroyers in 2025. Each displaces more than 5,000 tonnes, can carry nuclear weapons, and marks the first use of vertical launch system (VLS) cells in North Korean naval service. One of the vessels, Kang Kyon, was relaunched after capsizing and partially sinking during a failed launch attempt.
Underwater, North Korea has inducted two Sinpo/Gorae-class diesel-electric submarines since the 2010s, both capable of launching SLBMs or ICBMs. Beyond these, the bulk of the country’s roughly 100-strong submarine fleet – including midget submarines – consists of platforms that are several decades old, with unclear maintenance and readiness levels.
State media has claimed that the new SSBN will enhance North Korea’s nuclear second-strike capability at sea and form part of a wider strategy to strengthen its limited but evolving maritime power projection capabilities.