South Korea has taken its first historic step toward developing a homegrown nuclear-powered submarine, a 30-year aspiration considered essential to completing the nation's self-reliant defense posture. The government has designated the project as a core defense acquisition program — rather than a classified black program — and aims to launch the lead vessel in the mid-2030s. The announcement is expected to accelerate the project, which had drawn concerns over slow follow-up consultations since the leaders of South Korea and the United States agreed on the submarine's construction last November.
The Ministry of National Defense unveiled the "Basic Plan for the Development of the Republic of Korea's Nuclear-Powered Submarine" at the first Future Defense Strategy Committee meeting held in Jinhae, South Gyeongsang Province, on the 26th, naming the program "Jangbogo-N." Defense Minister Ahn Gyu-back said, "The government has identified 11 core tasks, including budget allocation, organizational structuring and special legislation, to secure the nuclear submarine," adding, "To systematically pursue these, we have launched a pan-governmental task force led by the Ministry of National Defense and involving 10 related ministries and agencies."
Minister Ahn continued, "The Korean nuclear-powered submarine, equipped with conventional armament, will play a critical role in countering North Korea's submarine-based nuclear missile threat through long-duration submersion capability and stealthy yet rapid mobility."
The government also presented five principles for systematically and gradually developing the Jangbogo-N program: ▲use of low-enriched uranium ▲domestic development and construction ▲utilization of domestic nuclear reactor and shipbuilding technology ▲safe management throughout the entire process ▲launch of the first vessel in the mid-2030s.
The nuclear submarine reactor will use low-enriched uranium (with enrichment levels below 20%) and will be developed for long-cycle operation to minimize fuel replacement. The submarine will be developed and built in Korea to ensure independence and stability in acquisition, maintenance and repair.
The government also plans to actively leverage world-class technology accumulated over many years in the civilian nuclear sector to ensure high reliability and safety. The plan calls for developing and managing the entire process — design, construction, operation, maintenance, nuclear fuel management and decommissioning — from a total lifecycle perspective to secure sustained operational capability. Finally, the lead nuclear submarine will be launched in the mid-2030s, with deployment to follow in the late 2030s.
A Defense Ministry official said, "Korea maintains a firm position that it will neither possess any form of nuclear weapons nor develop them," adding, "We will transparently and firmly fulfill our nuclear non-proliferation obligations based on international trust."
Once the Korean nuclear submarine enters service, South Korea will become the seventh country in the world to possess nuclear-powered submarines, following the United States, Russia, China, the United Kingdom, France and India. According to military authorities, the construction cost per submarine exceeds 2 trillion won, and the goal is to build at least four large nuclear submarines of 5,000 tons or more. They will be built as next-generation submarines based on the Jangbogo-III (KSS-III) Batch-II Jang Yeong-sil class (3,600 tons), a third-generation submarine independently designed and built in Korea.
A Navy official said, "If Korea acquires nuclear submarines, the most important role will be deterring North Korea's Gorae-class ballistic missile submarines," adding, "Looking more broadly at the Indo-Pacific, we can also expect deterrence effects against provocations from neighboring countries such as China."
France's Barracuda-class (Suffren-class) nuclear submarine has been mentioned as a role model for the Korean nuclear submarine. The 5,400-ton vessel costs about 1.6 trillion won to build. Given the similar size to the Korean nuclear submarine, France is expected to be a strong potential partner during development. The Barracuda-class nuclear submarine has a safe diving depth of 400 meters, a maximum underwater speed of 25 knots (46 km/h) and a surface speed of 14 knots (26 km/h), with a crew of 60. It can conduct operations for up to 70 days.
Two main interpretations have emerged regarding why the government publicly declared the Korean nuclear submarine development program. First, analysts say the move is intended to convey both domestically and internationally the government's commitment to establishing self-reliant defense, in tandem with the transfer of wartime operational control, which the current administration is pursuing as a core policy task.
Another interpretation is that the announcement is aimed at gaining an edge in the bidding war for Canada's Patrol Submarine Project (CPSP), worth up to 60 trillion won, where Korea is fiercely competing with Germany, by demonstrating submarine development capabilities and strengthening its military standing in the Indo-Pacific region.
Military experts said, "Pursuing the Korean nuclear submarine program signifies the completion of self-reliant defense and will serve as an opportunity to elevate Korea's military standing to a higher level," adding, "Possessing nuclear submarines will not only enhance response and deterrence capabilities against North Korea's nuclear and missile provocations but also strengthen the capacity to check China on behalf of the United States in the Indo-Pacific region."
