Envoy Stephen Bosworth, who made the first trip by a U.S. officials to Pyongyang since North Korea carried out a nuclear weapons tests and other provocative moves, including a series of missiles tests.
The United States is seeking to convince North Korea to return to the six-party talks regarding the denuclearization of the Korean Peninsula. In addition to Pyongyang and Washington, six-party talks include China, Japan, Russia and South Korea. They have been on hold since North Korea walked away last spring.
"It remains to be seen when and how (North Korea) will return to the six-party talks," Bosworth said Thursday at a news conference in Seoul.