South Korea’s new chief envoy to the six-party nuclear talks Lim Sung-nam has met with U.S. Deputy Secretary of State Bill Burns in Washington.

The two officials met on Thursday, local time, and analyzed North Korea’s stance that was unveiled during the second inter-Korean denuclearization talks in Beijing last month. Based on the analysis, the two officials discussed when it would be appropriate to hold follow-up North Korea-U.S. talks and follow-up South-North talks.

Lim and Burns also discussed possible messages that Washington and Seoul would convey to Pyongyang via the South Korea-U.S. summit set to open in Washington next Thursday.

Diplomatic sources said South Korea believes the second round of inter-Korean denuclearization talks were significantly useful. Sources added that the South plans to seek follow-up talks with the North while the U.S. pursues follow-up talks with Pyongyang as well with the aim of seeing the North implement preconditions for denuclearization.