South Korea, US in talks over nuclear planning, tabletop exercise

The plan came amid South Korean President Yoon Suk-yeol's push to strengthen American extended deterrence - the U.S. military capability, especially its nuclear forces, to deter attacks on its allies - since taking office in May, in the face of evolving North Korean threats.

In a newspaper interview released on Monday, Yoon said the allies are discussing joint nuclear planning and exercises and that would help clear doubts about the extended deterrence, with its existing concept "falling short of convincing" South Koreans.

"In order to respond to the North Korean nuclear weapons, the two countries are discussing ways to share information on the operation of U.S.-owned nuclear assets, and joint planning and execution of them accordingly," Yoon's press secretary, Kim Eun-hye, said in a statement.

The two leaders "tasked their teams to plan for an effective, a coordinated response to a range of scenarios, including nuclear use by North Korea, and so that is what the teams are working on," White House spokesperson Karine Jean-Pierre said.

A senior U.S. administration official elaborated, adding that both sides are looking at enhanced information-sharing, joint contingency planning and an eventual tabletop exercise following a request from their presidents after a meeting in Cambodia in November to explore ways to address North Korea's threats.

But the official noted regular nuclear exercises would be "extremely difficult" because South Korea is not a nuclear power, echoing the comment from U.S. President Joe Biden late on Monday that the allies were not discussing such activities. U.S. policy does not allow for the joint control of nuclear assets anywhere in the world.

"This is going to be done through a variety of ways, including as President Yoon said, through enhanced information-sharing, joint planning and expanding the range of contingencies that we plan for, as well as training, and with the idea eventually leading up to a tabletop exercise," the U.S. official told Reuters.

The timing of the planned exercises has not been finalised, but they would take place "in the not-too-distant future" and cover scenarios including but not limited to nuclear situations, the official said.

"The idea is to also try and make sure that we're able to fully think through the range of possibilities based on the DPRK capabilities which they've demonstrated, as well as their statements," that official added, using North Korea's official name, the Democratic People's Republic of Korea.

When asked about the tabletop exercises, a spokesperson for South Korea's defence ministry said talks were under way but declined to provide details.

The two countries have revived consultations on extended deterrence this year after a years-long hiatus while North Korea increased its nuclear and missile capability.

Pyongyang defined South Korea as an "undoubted enemy" and vowed to beef up its nuclear arsenal this year, after firing a record number of missiles in 2022 and fuelling tension by sending drones into the South in December.

"The U.S. countermeasures have not kept up with the North's advancing nuclear programmes, and the extended deterrence strategy is almost no different from when their nuclear capability was insignificant and weaker," said Go Myong-hyun, a research fellow at the Asan Institute for Policy Studies in Seoul.

But Kim Dong-yup, a professor at Kyungnam University, said the comment from Biden, who has sole authority to authorise the use of U.S. nuclear weapons, suggests an American reluctance to share nuclear operations, given their sensitivity and security concerns.

"Given growing voices for tactical nuclear weapons, Washington could try to give reassurances and send more nuclear assets when we want, but they're unlikely to fully materialise President Yoon's push for greater extended deterrence," Kim said.