SEOUL - A US State Department envoy's visit to Pyongyang this week could help set the stage for six-party talks on North Korea's nuclear programmes later in May, South Korea's Yonhap news agency said on Monday.

North Korea failed to disclose an inventory of its nuclear activities when it was due on Dec 31, slowing the implementation of a 2005 deal under which Pyongyang pledged to abandon all nuclear programmes in return for aid and diplomatic recognition.

The State Department's Sung Kim, who last visited the communist state's capital in late April, is expected to wrap up coordination on the nuclear declaration, Yonhap said.

Once the talks with the US envoy are finalised, North Korea is expected to submit the nuclear report to China which then will distribute details to the countries involved in the six-nation talks, Yonhap said.

The six-party agreement on the North's nuclear disarmament was hammered out among the two Koreas, the United States, China, Japan and Russia.

'Unless an unexpected variable shows up, it is possible to hold a six-party meeting late this month,' the source told Yonhap.

The North's delay in the declaration of its activities was partly due to reluctance to discuss any suspected transfer of nuclear technology to Syria and to account for its suspected pursuit of uranium enrichment, analysts have said.

Last month, the United States released intelligence about suspected North Korea-Syria nuclear collusion in a move President George W. Bush said was aimed partly at putting pressure on Pyongyang.