A U.S. diplomat has traveled to North Korea for talks to break the latest deadlock in the Korean Peninsula's nuclear negotiations.
The U.S. Embassy in Seoul said Thursday that the US State Department's top Korea expert, Sung Kim, travelled to North Korea by land across the heavily fortified inter-Korean border.
U.S. Deputy Secretary of State John Negroponte, who arrived on Wednesday in South Korea, said he would not go into details of the visit.
"I'd rather not comment on the details of his visit there, except to say that this is part of an ongoing process connected with the six-party talks, and particularly with the phase concerning the denuclearisation, and this is part of that process, and we'll have to wait and see what that brings."
Kim was to stay in North Korea for three days to discuss Pyongyang's obligation to declare all its nuclear programs.
Negotiations have been stalled over the North's failure to deliver its promised nuclear declaration.
Washington has accused the North of refusing to address suspicions it pursued a uranium-based nuclear program and transferred nuclear technology to Syria.