North Korean and United States negotiators headed to Singapore Monday on the eve of key talks aimed at ending a months-long impasse over the communist state's nuclear disarmament.
The United States has played down the possibility of a breakthrough in Tuesday's talks between US envoy Christopher Hill and North Korea's Kim Kye-Gwan, but Hill said at the weekend he was hopeful progress would be made.
Washington has been pushing North Korea to come clean on its entire nuclear programme as a key step in a 2007 six-nation denuclearisation deal that also involves China, Japan, Russia and South Korea.
South Korean media reports have suggested that Kim could be prepared to hand over a document at the Singapore talks that addresses concerns about its alleged secret uranium enrichment programme and cooperation with Syria.
Kim was scheduled to arrive in Singapore on Monday afternoon from Beijing, diplomatic sources said, while Hill was expected in the early evening from Indonesia, where he attended a conference last week.
The pair last met in Geneva in mid-March.
The 2007 six-party deal grants North Korea -- which tested an atomic weapon in 2006 -- energy aid and major diplomatic and security benefits in return for full denuclearisation.
The current phase of the deal required the North to disable its main plutonium-producing plants and declare all nuclear activities by the end of 2007.
The North says it submitted the declaration last November. But the United States says it has not accounted for an alleged secret uranium enrichment programme or for alleged proliferation to Syria.
In Seoul last week, Hill said the United States knows the North "was engaged in the procurements of things for uranium enrichment."
"We need to know the status of that. Also, we need to know what is going on with any foreign nuclear cooperation," he added.
"We have some ambitions for trying to get done with this, get through this in 2008," he said.
South Korea's Hankyoreh daily, which reported that a breakthrough could be in the offing, said the US had vowed not to make public the so-called "confidential minute" and not to exploit it for political purposes.
"We'll see if North Korea is ready to discuss a declaration," Hill said during a stop in East Timor on Sunday, expressing hope that the two sides would "make some progress on that, and then we can maybe move on."
South Korea's Yonhap news agency quoted a South Korean foreign ministry official as saying there were expectations that Kim would "bring an answer acceptable to the US".
But the talks coincide with increasing tensions between the two Koreas since conservative Lee Myung-Bak became president of the South in February. He has angered the North by adopting a tougher line on relations.
North Korea kept up the rhetoric on Monday, accusing Lee of pushing the peninsula closer to nuclear war and telling Seoul it should order the United States to withdraw its "nuclear weapons massively stockpiled in South Korea."
The US, Seoul's long-time military ally, says it withdrew the last of its atomic weapons from the peninsula in 1991.
On Thursday, North Korea announced it was suspending all dialogue with the South and closing the border to Seoul officials.
During his visit to Indonesia, Hill called the comments "very inappropriate and very unhelpful to the situation."
Hill was to meet with Singaporean officials late Monday ahead of Tuesday's discussions with Kim, US officials said.
Nobody answered the telephone on Monday at North Korea's embassy in Singapore. The two countries have had diplomatic relations since 1975. (AFP)
US and North Korea to hold key nuclear talks