Bloomberg: US, South Korea hold secret talks on joint nuclear submarine program

The United States and South Korea are engaged in confidential discussions on a potential joint effort to build nuclear-powered submarines for both nations’ navies, a move that could significantly deepen their military alliance beyond the agreement announced by the two countries’ presidents earlier this month, sources familiar with the matter told Bloomberg.

In late October, President Donald Trump and South Korean President Lee Jae Myung met in South Korea and publicly unveiled a pact allowing South Korea to construct its own nuclear-powered submarines. At the time, Trump stated that the vessels would be built in Philadelphia. Since that announcement, insiders say, a broader plan has emerged behind the scenes.

A joint fact sheet outlining their overall trade, tariff, and defence agreement was released on the evening of Thursday, November 13, in Washington and the following morning in Seoul. While it mentioned the construction of nuclear submarines, it provided no further specifics, suggesting that many key points remain unresolved.

Sources indicate that officials from both countries are exploring a plan for Korean-led joint production of submarines for both nations, potentially across sites in South Korea and the United States. The early-stage concept could initially use U.S.-class submarine designs, which remain highly classified, before eventually transitioning to submarines based on South Korea’s own designs.

The discussions are partly rooted in a private suggestion from President Trump. When South Korea requested the necessary permissions and nuclear capabilities to build its own submarines, Trump reportedly proposed that a few of the vessels could also be built for the U.S., as the country seeks to accelerate its submarine production.

The exact structure of any potential deal remains uncertain, and the negotiations could stall or fail entirely. Both sides are still in the early phases of discussions over fundamental questions, including which submarines will be built, where production will take place, the intended recipients, and the production sequence.

The joint fact sheet celebrated collaborative efforts aimed at “increasing the number of U.S. commercial ships and combat-ready U.S. military vessels as quickly as possible, including the potential construction of U.S. vessels in the ROK [Republic of Korea].” It also noted: “The United States has given approval for the ROK to build nuclear-powered attack submarines. The United States will work closely with the ROK to advance requirements for this shipbuilding project, including avenues to source fuel.” The document, however, did not mention Philadelphia.

While the official statement avoided detailing the ongoing talks, any agreement between Washington and Seoul could significantly reshape the U.S.-South Korea military alliance and might resemble the Aukus arrangement that provides Australia with nuclear-powered submarines. Yet the proposed deal is unprecedented in other ways and faces numerous challenges, questions, and potential obstacles.

For President Trump, the submarine discussions form part of a larger trade and investment negotiation, which includes reducing certain tariff rates on South Korean goods in exchange for a $350 billion investment fund, $150 billion of which is earmarked for shipbuilding. Trump is seeking to leverage South Korea’s shipbuilding expertise to rejuvenate the U.S. sector, encompassing both submarines and commercial vessels.

During a televised briefing on the fact sheet, President Lee emphasised that South Korea had remained firm throughout negotiations to finalise the overall trade and tariff agreement following Trump’s visit.

“The U.S. government maintained that the general framework had already been settled during the summit. But when it came to drafting the detailed text, they presented a wide range of differing opinions,” Lee said. “The lengthy process was unavoidable — it was the only way we could fully exercise the one power we had, which was to hold firm.”

By Tamilla Hasanova