Trump had announced that South Korea would build the submarine in a Philadelphia shipyard "right here in the good ol' U.S.A.", where the nuclear technology is among the most sensitive and tightly guarded military secrets.
It comes after Seoul announced the two countries had reached a broad deal covering investment and shipbuilding, following Trump's meeting with South Korean President Lee Jae Myung.
Critics argue that, given Trump's remarks, Washington may push Seoul to invest in the Philadelphia shipyard in exchange for US support to build the vessel.
But South Korea's Defence Minister Ahn Gyu-back said Wednesday it was sensible to build the submarine at home, his ministry said.
When asked by lawmakers at the National Assembly whether he believed it should be built domestically, Ahn replied: "We believe it is reasonable, given that we have accumulated more than 30 years of technology and research."
Unlike diesel-powered submarines, which must regularly surface to recharge their batteries, nuclear-powered ones can remain submerged for far longer.
Senior defence ministry official Won Chong-dae said this week it was "feasible to construct a nuclear-powered submarine with our own technology".
Seoul expects to launch the lead vessel by the mid to late 2030s, if Seoul secures "the submarine fuel through consultations with the United States" and begins construction by the late 2020s, he added.
Won's comments followed remarks by national security adviser Wi Sung-lac, who said Seoul had sought and received Washington's "authorisation for the raw materials", without mentioning US submarine technology.
Wi told lawmakers on Thursday that Seoul "is not considering building a submarine in the US at the moment", and that "we were thinking about building it ourselves".
He also said that it "wouldn't be realistic to invest in submarine facilities" in the US shipyard.
The Philadelphia shipyard has been run by South Korea's Hanwha Ocean since last year, but minister Ahn said the yard is judged to be "currently lacking sufficient technology, workforce, and facilities".
President Lee said this week that once South Korea's own military capabilities grow, "America's defence burden in the Indo-Pacific will also be reduced".
Seoul says nuclear submarine possible within 15 years after US nod
Seoul (AFP) Nov 4, 2025 -
South Korea expects to launch its first nuclear-powered submarine by the late 2030s, a senior defence ministry official told ministers on Tuesday, days after Washington had approved Seoul's plans.
US President Donald Trump last week said he had given ally Seoul a green light, after South Korea had announced that the two countries reached a broad deal covering investment and shipbuilding.
Trump, who was in South Korea for a regional summit, said on Truth Social that Seoul would manufacture its nuclear-powered submarine in "the Philadelphia Shipyards, right here in the good ol' U.S.A."
US nuclear submarine technology is considered among the most sensitive and tightly guarded military secrets.
Unlike diesel-powered submarines which must surface regularly to recharge their batteries, nuclear-powered ones can remain submerged for far longer periods of time.
Seoul has not commented on Trump's remarks suggesting the submarine would be built on US soil.
Senior defence ministry official Won Chong-dae, however, said on Tuesday that it was "feasible to construct a nuclear-powered submarine with our own technology".
"If we secure the submarine fuel through consultations with the United States and enter the construction phase in the late 2020s, we expect to launch the lead vessel by the mid to late 2030s," Won told a cabinet meeting.
"South Korea already possesses world-class design and construction capabilities for conventional submarines," he said.
His remarks came after a South Korean presidential aide said Seoul had sought Washington's "authorisation for the raw materials" and received approval.
- Denuclearisation 'pipedream' -
The Philadelphia shipyard mentioned by Trump has been run by South Korea's Hanwha Ocean since last year, but media reports say it lacks the facilities and equipment needed to build nuclear-powered submarines.
In August, Hanwha Ocean announced a $5 billion investment in the shipyard, describing it as part of Seoul's commitment to supporting shipbuilding growth in the United States, which Trump has pushed for.
Pentagon chief Pete Hegseth, who visited the border between the two Koreas earlier this week, said on Tuesday that Seoul has "an incredible shipbuilding industry which we look forward to partnering with a lot more."
Since North Korean leader Kim Jong Un's 2019 summit with Trump collapsed over the scope of denuclearisation and sanctions relief, Pyongyang has repeatedly declared itself an "irreversible" nuclear state.
It has since forged closer ties with Russia, sending troops to support Moscow's war in Ukraine, and did not respond to Trump's offer to meet with Kim last week.
Pyongyang also dismissed Seoul's hopes for denuclearisation as a "pipedream" which "can never be realised".
Seoul's Defence Minister Ahn Gyu-back said Tuesday that denuclearisation of the Korean Peninsula "remains an unwavering commitment", and ruled out South Korea ever possessing nuclear arms.
Related Links
Naval Warfare in the 21st Century
| Subscribe Free To Our Daily Newsletters |
| Subscribe Free To Our Daily Newsletters |
