Even so, the fate of the six-country negotiations hangs in the balance because Pyongyang does not seem prepared to enter discussions just yet, Foreign Office Minister Bill Rammell told reporters after a three-day visit to North Korea.

"The North Koreans were saying they were still committed to the six-party talks process but weren't prepared to commit to a date," he said during a stopover in Beijing.

Talks on Pyongyang's nuclear ambitions, involving the two Koreas, the United States, China, Japan and Russia, were scheduled before the end of September.

But the British minister said North Korean officials had cited "adverse developments" since the last round of six-party talks in Beijing in June as one reason they were reluctant to return to a new round.

"Certainly one of the factors that I think they are considering, and I discussed this issue with them in detail, is the timing of the American presidential elections,"he said.

Rammell said he told his hosts that US policy is unlikely to change greatly regardless of who wins in November.

Rammell also said Foreign Minister Paek Nam-Sun had told him last week's explosion near the country's border with China was an intentional, non-nuclear detonation of a mountain to prepare for a hydro-electric project.

At Rammell's request, North Korea had given the green light for Britain's ambassador to Pyongyang David Slinn to lead a team on a visit to the site, with all heads of mission in Pyongyang allowed to participate.

"I do regard that movement as a limited and positive step in terms of opening up in the right direction," Rammell said.

He also welcomed North Korea's willingness to explain the cause of the blast, "because often in the past in similar circumstances North Korea hasn't given an explanation."

Slinn told AFP by telephone from Pyongyang that the North Koreans appeared to be cooperating with his plans for the trip.

"We all felt that they are cooperating with us but it will take some time," he said. "We hope that within a few days we can go."

South Korea's Defense Minister Yoon Kwang-Ung said a visit by the diplomats and new satellite images would help clear up the mystery.

"Let's wait, as North Korea has admitted there was a blast and allows foreign diplomats to get access," he said. "We should not be concerned much if it was not a nuclear test."

South Korea's Yonhap news agency first reported the explosion on Sunday, quoting diplomatic sources as saying it triggered a mushroom cloud across a remote and mountainous area of North Korea.

The agency said the blast occurred in Kimhyungjik county in the province of Ryanggang near the Chinese border on the day when North Korea marked the 56th anniversary of its founding.

The area where the latest blast occurred is home to an underground base for missiles and a suspected plant for enriching uranium, according to experts.

An added element of uncertainty over the six-party talks has emerged with Seoul's recent admission that South Korean scientists carried out nuclear experiments.

But Rammell said in Beijing that what had happened in South Korea was "very, very different" from North Korea's ambitious and secretive program, giving Pyongyang no excuse to refuse to talk.

The minister urged North Korea to follow the example of Libya, which has announced it is abandoning its program for weapons of mass destruction after secret talks with Britain and the United States.

Pyongyang refused, saying it did not see the Libyan example as "comparable" to North Korea, he said.

burs-ph/mp/sm

All rights reserved. © 2005 Agence France-Presse. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by Agence France-Presse. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of Agence France-Presse.