South Korean President Moon Jae-in's special envoys will embark on a two-day visit to North Korea on Monday afternoon aimed at brokering dialogue between Washington and Pyongyang, officials here said.
Pyongyang officials lashed out at the U.S. after President Donald Trump demanded the hermit state get rid of all its nuclear weapons before his diplomats enter into negotiations.
"There's a clear determination on Moon's part not to lose momentum after the Olympics", said Euan Graham, the director of the worldwide security program at the Lowy Institute, an Australian think tank.
That demand is unrealistic - it asks North Korea to discard its ace of spades before the game begins.
Trump suggested on Saturday that the United States would be meeting with North Korea but he had told Pyongyang it must first "denuke".
The envoys will then travel to Washington to discuss the result of the meeting, Yoon said, adding that South Korea will closely coordinate with Japan and China.
The 10-member delegation, headed by National Security Office (NSO) head Chung Eui-yong, will depart South Korea at approximately 0500 GMT from Seoul Air Base in Seongnam City near Seoul, the official said on condition of anonymity.
The delegation is expected to hold talks that would pave the way for a possible summit meeting between the leaders of South and North Korea after Kim Jong-un last month invited Mr Moon to visit Pyongyang. She was in South Korea last month to attend the Winter Games opening ceremony. The South Korean envoys will visit the United States after their talks to brief officials.
Sending Suh to Pyongyang "suggests they're already taking about summit preparations", said Graham.
Suh Hoon, director of the National Intelligence Service (NIS), the country's spy agency, is included in the delegation along with Vice Unification Minister Chun Hae-sung, Second Deputy NIS Director Kim Sang-gyun, and Yun Kun-young, a senior Blue House official.
The majority of North Koreans are negative about their country's nuclear weapons program, with many of them saying it is not a source of national pride or prosperity, a USA survey showed Friday.
Trump appears, however, to have been constrained by the advice of Defense Secretary Jim Mattis, who has warned of a second Korean War breaking out if the North retaliated by bombarding the Seoul and Incheon metropolitan region with artillery well hidden just above the demilitarized zone between the two Koreans.
But critics contend the Trump administration hasn't offered a clear, coherent message on diplomacy with the Kim regime.
"A couple days ago they said we would like to talk, and I said, so would we, but you have to de-nuke, you have to de-nuke. I think it will be a chaotic year for elections with a number of [referendum] topics", Lu said. You have to de-nuke.' So let's see what happens.
The White House's statement following the Trump-Moon phone conversation said the two leaders "noted their firm position that any dialogue with North Korea must be conducted with the explicit and unwavering goal of complete, verifiable and irreversible denuclearization".
"The dialogue we desire is the one created to discuss and resolve the issues of mutual concern on an equal footing between states", the spokesman said.