North Korea has hinted it may be prepared to discuss its reported nuclear weapons programme with the United States, according to South Korean media reports.

If the United States is willing to withdraw its hostile policy... the North also is ready to resolve security concerns through dialogue

North Korea's Kim Yong-nam as quoted by Southern media

If confirmed, the remarks would be the first official North Korean response to a US statement last week that Pyongyang had admitted to developing a secret nuclear weapons programme in contravention of a 1994 accord.

The accord arranged for an international consortium to build two nuclear power reactors in return for North Korea ending its own programmes.

But it was further cast into doubt on Sunday by US Secretary of State Colin Powell, who said the nuclear agreement had been effectively "nullified".

US officials later played down the comment. Japan and South Korea, key members of the consortium, said they hoped the accord could be salvaged.

Correspondents say the accord is one of the few means of exerting leverage over the secretive North, and governments will be reluctant to give it up.

According to the South Korean media reports, North Korea's Kim Yong-nam - the country's nominal head of state - said:

"We consider the recent situation seriously. If the United States is willing to withdraw its hostile policy toward the North, the North also is ready to resolve security concerns through dialogue."

He was speaking with the leader of a South Korean delegation, Jeong Se-hyun, who is in the Pyongyang for talks between government delegations from the two Koreas.

Diplomatic pressure

The BBC's Charles Scanlon reports that the US is prepared to meet North Korea for talks but is insisting the Communist regime must close down its nuclear programme before any progress can be made.

A senior US envoy, James Kelly, is now in Japan on a regional mission to exert diplomatic pressure on the North to give up its nuclear weapons programme.

When you have an agreement between two parties and one says it's nullified - then it's hard to see what you do with such an agreement

Colin Powell US Secretary of State

He said North Korea must immediately dismantle the facilities in a way that would be clearly visible to the outside world.

Mr Powell said Washington would consult with allies before deciding on the future of the 1994 deal, under which the US provides fuel and assistance with building the power stations.

But Mr Powell said the US had no plans to launch military action against North Korea when asked if the situation was comparable to Iraq, which Washington accuses of developing nuclear weapons.

North Korea's official media blamed the US for delays which had put the accord at risk.

"The provision of the light-water nuclear reactor is greatly delayed and (the agreement) has arrived at a critical juncture of whether to scrap it," said Radio Pyongyang.