The US envoy for North Korea is set to visit South Korea on Sunday for working-level talks to prepare for a second summit between the US and the North's leaders slated for late this month, sources said.

Special Representative Stephen Biegun will make a three-day visit to Seoul for talks with his North Korean counterpart Kim Hyok-chol, a former ambassador to Spain, to discuss agenda items for a summit between US President Donald Trump and North Korean leader Kim Jong-un, they added.

They may have a meeting at the border village of Panmunjom as early as Monday. Before the talks, Biegun plans to meet Lee Do-hoon, South Korea's top nuclear envoy, to coordinate their stance on North Korea's denuclearization.

Trump said last week that a date and venue for his summit with Kim will be announced this week. The summit will be held in late February, possibly in Vietnam.

The nuclear envoys of Washington and Pyongyang are expected to discuss details about denuclearization steps that the North should take and corresponding measures from the United States.

During US Secretary of State Mike Pompeo's October trip to Pyongyang, the North's leader promised that the regime would dismantle and destroy all of its plutonium and uranium enrichment facilities in exchange for US corresponding measures, Biegun said last week during a speech at Stanford University.

Trump and Kim held their historic first summit in Singapore in June last year and agreed to work toward complete denuclearization of the Korean Peninsula in exchange for security guarantees for Pyongyang.

But the denuclearization talks had been at an impasse, with the North calling for sanctions relief and corresponding measures by the US for the denuclearization steps that it has taken so far, such as the dismantling of a nuclear test site.

Washington, however, has insisted that sanctions and pressure will be maintained until North Korea implements sincere denuclearization measures, including declaring a list of its nuclear weapons.

Biegun said last week that the North's full declaration of its nuclear and missile programs will be required to acknowledge complete denuclearization of the regime.

(Yonhap)