Top nuclear envoys of the two Koreas have met in Beijing to lay the groundwork for resuming the six-party talks.

South Korean negotiator Chun Yung-woo said Tuesday that he had frank and open discussions with North Korean chief negotiator Kim Kye-kwan, calling them a basis for progress in the next round of six-party talks.

Asked about a recent meeting with U.S. nuclear envoy Christopher Hill in Berlin, Kim told reporters that the U.S. showed a shift in its stance on the North Korean nuclear issue.

Chun and Kim each met one-on-one with Chinese Vice Foreign Minister Wu Dawei to discuss the agenda and timetable for the six-party talks after arriving in Beijing Monday.

The North Korean official reportedly changed his plan to return to Pyongyang Tuesday morning to meet with South Korea's Chun.