North Korea named a former army officer who led military and high-level talks between the two Koreas as its top diplomat, Yonhap News reported, in a move that could change the course of stalled nuclear negotiations between Kim Jong Un and U.S. President Donald Trump.

Foreign envoys in Pyongyang were notified late last week that Ri Son Gwon replaced Ri Yong Ho as foreign minister, Yonhap said, citing various sources it didn’t identify. Ri Yong Ho had served as the top diplomat since 2016.

South Korea’s Unification Ministry said in a text message that the government is trying to confirm whether the foreign minister was replaced and Ri Son Gwon’s official title has been changed. The move, which is yet to be announced in North Korea’s state media, is likely to be confirmed to resident diplomats at an event scheduled for Jan. 23 in Pyongyang, NK News reported separately.

Ri Son Gwon, former chairman of the Committee for the Peaceful Reunification of the Fatherland, became known to South Koreans after he led a delegation to high-level inter-Korean talks in January 2018. He was accused of being rude to a visiting group of South Korean conglomerate chiefs later that year, appearing to rebuke them for not taking enough action to boost business development between the two sides.

The apparent replacement comes days after the isolated nation publicly declared that it won’t rely on its leader’s personal relationship with Trump as it doesn’t intend to trade its nuclear weapons for a halt in sanctions.

Since the failure of working-level denuclearization talks in October in Stockholm, Pyongyang hasn’t responded to Washington’s continued demands for another talk and instead stepped up tensions verbally and with weapons tests.

‘Crucial’ Test

Most recently, it said late last year that it successfully conducted a “crucial” test at a long-range projectile launch site and had boosted its nuclear-deterrent capabilities, without elaborating on details.

Kim declared in a speech at the start of the year that a lack of U.S. response in nuclear talks meant he was no longer bound by his pledge to halt major missile tests and would soon debut a “new strategic weapon.” Declining to go into detail, Kim also left the outside world guessing what “new path” he will take, and how he will deal with the U.S. in 2020.

Ri Son Gwon served as a senior colonel in 2010 and last appeared in the North’s state media when the KCNA reported in April he was elected as a member of the Foreign Affairs Committee along with Choe Son Hui, first vice-minister of foreign affairs. He previously also led a working-level military dialogue between the two Koreas in 2011.

Ri has no direct experience of dealing with the U.S., nor is an official with the traditional elite-diplomat background, said Cheong Seong-chang, a researcher at the Sejong Institute in South Korea, casting doubts over a possible breakthrough in the U.S.-North Korea talks.

“I think the North will take a harder line against the U.S.,” Cheong said. It “will be under greater influence of the military, which has urged to strengthen its position as a nuclear power,” he said.

The replacement of foreign minister also coincides with Seoul’s sudden turn to improve inter-Korean ties as the Kim-Trump talks for denuclearization remain in deadlock and rising cracks in South Korea’s relations with the U.S.

South Korean President Moon Jae-in said he would help on projects such as individual tourism with North Korea if they require approval from the United Nations to exempt them from sanctions. His Unification Ministry later said the government is considering allowing South Korean individuals to travel to North Korea to expand inter-Korean exchanges in the private sector.

U.S. Ambassador to South Korea Harry Harris said such a push by Seoul should be discussed with the U.S., and his comment was immediately denounced by Moon’s office as “very inappropriate.”

(Updates with comments from South Korea’s Unification Ministry and analyst from third paragraph)

To contact the reporter on this story: Kanga Kong in Seoul

Shamim Adam, Virginia Van Natta, Jiyeun Lee