Park Ji-won is a writer for The Korea Times who has been covering a wide range of topics from Korea’s culture to its politics. An avid journalism enthusiast to the core, Ji-won brings a thoughtful and unique perspective to every topic she covers. On weekends, you'll often find her contemplating life’s purpose on a yoga mat — with a cup of quality tea in hand. A native Korean speaker by birth and fluent in English through her work, she went to college in Japan and is learning Chinese and French — hoping to add Polish, Russian and Thai to the mix.
S. Korea, US align on nuclear submarines as Seoul steps up peninsula defense
First Vice Foreign Minister Park Yoon-joo, right, shakes hands with U.S. Under Secretary of State for Political Affairs Allison Hooker at the Ministry of Foreign Affairs headquarters in central Seoul, June 2. The U.S. delegation led by Hooker and the Korean delegation led by Park launched formal negotiations to implement security and economic agreements reached during the October 2025 summit between President Lee Jae Myung and U.S. President Donald Trump. Courtesy of Ministry of Foreign Affairs
By Park Ji-won
South Korea and the United States reached a shared understanding during last week's bilateral talks that Seoul's future nuclear-powered submarines will both bolster the security framework on the Korean Peninsula and benefit the broader alliance, the foreign ministry said Tuesday.
“We continued the discussions based on the understanding that the submarines will be built in South Korea and the U.S. side didn’t elaborate further,” a foreign ministry official said, adding that the U.S. delegation did not link the submarine issue to the transfer of wartime operational control (OPCON), another critical area of focus for the two allies.
The remarks came a week after the kickoff meetings in Seoul on June 2 and 3, aiming at implementing security and economic agreements outlined in the joint fact sheet published in November 2025, following the October 2025 summit between President Lee Jae Myung and U.S. President Donald Trump. The meetings were led on the Korean side by First Vice Foreign Minister Park Yoon-joo and on the U.S. side by Under Secretary of State for Political Affairs Allison Hooker, and involved officials from both countries' national security, defense, energy and trade bodies.
South Korean President Lee Jae Myung meets with U.S. President Donald Trump on the sidelines of the Asia-Pacific Economic Cooperation summit in Gyeongju, North Gyeongsang Province, Oct. 29, 2025. Reuters-Yonhap
The talks came at a critical juncture, with North Korea continuing to expand its nuclear arsenal while deepening ties with China, a partner that largely condones Pyongyang's nuclear stance. Pyongyang has continued to flaunt its expanding strategic capabilities, recently unveiling a high-end nuclear-powered submarine capable of carrying nuclear warheads.
At the 2025 summit, Lee and Trump agreed to pursue nuclear-powered submarines for South Korea, with Seoul also pledging to invest $350 billion in the U.S. in exchange for reduced tariff rates. Although negotiation details remain confidential, the talks are understood to have centered on the scope of U.S. approval for South Korea's uranium enrichment and spent fuel reprocessing capabilities. Seoul aims to build the submarines in Korea and purchase nuclear fuel from the U.S.
Three potential paths for implementing the negotiations have been widely discussed: a full revision of the Section 123 Agreement on civil nuclear cooperation, a partial amendment to the accord, or the enactment of new enforcement decrees. While the South Korean side is said to be open to all options, its current focus remains strictly on the core substance of the negotiations.
President Lee Jae Myung receives a briefing from the defense ministry on the government's plan to develop nuclear submarines at a naval base in Changwon, South Gyeongsang Province, May 26. Yonhap
The deal itself made headlines as U.S. Congress and Washington think tanks continue to raise concerns on nuclear proliferation, arguing that granting South Korea uranium enrichment capabilities could inadvertently pave the way for nuclear weapons development.
After the two-day talks, Hooker described the meeting as a “success.”
“Headed back to Washington after a brief but very productive visit to Seoul. Our initial discussions on U.S.-ROK nuclear cooperation were a success and set the stage for continued technical conversations. As we open new areas of cooperation, we continue to push for progress on existing economic and security related issues … We’ve set ambitious goals, but our alliance is up to the task!” she wrote on social media platform X, formerly Twitter, on June 3.
The two sides agreed to accelerate their negotiations to come up with substantive results as early as possible, the official added. The National Security Councils of both nations are expected to hold several plenary sessions in the future, alongside frequent working-level visits by delegations to negotiate specific areas such as uranium enrichment, spent fuel reprocessing and nuclear submarine cooperation.