Christopher Hill met Chinese officials on Monday before heading to South Korea on Tuesday and Japan later in the week, according to Hill and US Embassy staff.

Mr Hill told reporters late on Monday that he did not rule out meeting North Korean representatives during his stay in the Chinese capital.

'We always let them know that I'm here. We don't have anything set up yet.'

'But, you know, it is possible. I'm here tomorrow (Tuesday), but we don't have any meetings scheduled as yet,' Mr Hill said.

Mr Hill's visit is aimed at laying the groundwork for Dr Rice's trip, which will focus on the deadlocked process to dismantle North Korea's nuclear facilities, a US State Department spokesman said over the weekend.

Dr Rice will leave Washington on February 23 for South Korea, China and Japan, her spokesman said last week.

The North was supposed to disable its main atomic plants by December 31 and list all its programmes under the six-nation deal negotiated by the two Koreas, China, the United States, Russia and Japan.

North Korea has said it submitted a list in November, but the United States says it is still waiting for a complete declaration including a full account of a suspected covert uranium enrichment programme.

North Korea, which staged a nuclear test in October 2006, has accused Washington of bad faith and warned it could slow down cooperation. -- AFP