The US point man on North Korea will be in Asia next month to discuss how to bring the communist state back into nuclear disarmament talks, officials said in Seoul on Sunday.
Stephen Bosworth's visit to the region comes as Pyongyang steps up its charm offensive with a series of conciliatory gestures, including the release of US and South Korean citizens held by the reclusive state.
The North on Saturday freed four South Korean fishermen it had detained for almost a month in the regime's latest overture to the outside world.
Seoul officials said they expect Bosworth to arrive in Asia in September, with the itinerary yet to be announced by Washington, but reaffirmed that he would not visit North Korea this time.
"North Korea keeps sending signals that it wants talks with the United States, which will be among the key agenda items to be discussed when the US envoy is here," a senior official told AFP on condition of anonymity.
"The Seoul government maintains that it does not oppose US-North Korean talks if they help bring North Korea back to six-party nuclear talks. Bosworth has no plan to visit Pyongyang this time."
North Korea in April quit the forum -- which groups China, the US, the two Koreas, Japan and Russia -- in protest at the UN Security Council's censure of its long-range rocket launch.
In May the North conducted its second nuclear test, incurring tougher sanctions that were even supported by its close ally China.
But the communist state has launched a charm offensive since early August when former US president Bill Clinton visited Pyongyang to win the release of two American journalists held there on charges of illegal entry.
The North has since set free a Seoul worker detained for five months on charges of criticising the communist state, lifted border restrictions for South Koreans and agreed to allow more reunions for families divided since the 1950-53 war.
Critics suspect the North is reaching out for talks, while trying to undermine international efforts to enforce UN-backed sanctions against it.
The State Department said last week Bosworth would head to East Asia "sometime soon" but said he "will not talk to North Korea."
South Korean media have said Bosworth and his team would probably visit South Korea, China and Japan in early September.