North Korea’s Foreign Ministry on Tuesday, 29 September 2026, warned of the implications of the United States’ approval of South Korea’s project to build its first nuclear-powered attack submarine, describing the move as a “dangerous development” that would add further instability to the political and military environment in the Asia-Pacific region.
Pyongyang criticises US support for project
In a statement published by North Korea’s state media, the ministry said US support for the South Korean project represented, in its words, an extension of Washington’s nuclear proliferation policy through the AUKUS security pact with Britain and Australia.
Pyongyang accused the United States of carrying out what it called a “radical nuclear weapons build-up”, saying US policies had contributed to the “collapse of the international nuclear order”. The comments came amid repeated North Korean criticism of expanded US cooperation with its allies on nuclear-powered submarines.
North Korea accused Washington on 16 September of seeking to expand what it called a “nuclear submarine alliance”, saying the AUKUS pact had become a model that the United States was seeking to transfer to other allies, including South Korea and Japan. Pyongyang linked these moves to the continued strengthening of its military and nuclear capabilities.
Seoul sets stages for Jang Bogo-III submarine
Seoul says the planned submarine will play a key role in countering nuclear and missile threats launched from North Korean submarines, benefiting from its ability to remain underwater for long periods, as well as its speed and range compared with diesel-electric submarines. Under South Korea’s plan, the submarines will use low-enriched uranium fuel and carry conventional weapons.
Seoul also intends to develop and build the submarine domestically, drawing on its capabilities in nuclear energy and shipbuilding. It plans to manage the design, construction, operation, maintenance, fuelling and decommissioning stages under an integrated programme covering the submarine’s life cycle.
US approval and consultations on submarine fuel
The project followed an official US announcement in November 2025 granting South Korea approval to build nuclear-powered attack submarines. The White House said at the time that Washington would work closely with Seoul to determine the project’s requirements, including possible ways to provide the necessary nuclear fuel.
On 23 September 2026, US President Donald Trump and South Korean President Lee Jae-myung affirmed during a meeting on the sidelines of the UN General Assembly that they would continue consultations on submarine fuel, enrichment, reprocessing and cooperation in shipbuilding, based on understandings announced by the two countries the previous year.
The South Korean government says developing the submarine is a national strategic project requiring cooperation among the defence, diplomatic, nuclear energy, industrial, science and technology sectors. Government agencies have also begun preparing the project’s legislative and regulatory frameworks, including nuclear safety systems and coordination with the International Atomic Energy Agency on non-proliferation obligations.
