South Korea has offered to mediate between the United States and North Korea to resolve the crisis over the North's nuclear programme.

The offer comes as Pyongyang restated its readiness to hold talks with the US as long as there were no preconditions.

But Washington has always rejected such direct talks with the Stalinist state until North Korea dismantles its nuclear facilities.

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So instead, South Korean President-elect, Roh Moo-hyun, has suggested that his country plays the role of broker.

Washington has consistently driven a harder line on North Korea than its regional allies, and has rejected compromise deals in the past.

North Korea has caused international alarm by preparing to restart its Yongbyon nuclear complex which was sealed as part of a 1994 deal to stop it developing nuclear weapons.

South Korea may convey a compromise proposal to the US when both countries meet, along with Japan, in Washington next week to discuss the crisis, South Korea's Yonhap news agency reported.

That proposal could involve asking the US to give North Korea a written assurance guaranteeing its sovereignty if Pyongyang first scraps its nuclear programme.

North Korea has repeatedly asked the US to sign a non-aggression pact, fearing a US attack.

President-elect Roh wants to keep the North engaged

North Korea's ambassador to China, Choe Kim-su, said Pyongyang would welcome outside mediation.

"If there's any country which aspires for security on the Korean peninsula and the peaceful solution of the nuclear issue, they should play a positive role," he told a press conference.

Southern anxiety

Correspondents say South Korea, perilously near to the unpredictable North, fears Washington's heavy-handed approach.

"President-elect Roh considers the nuclear issue as a matter of life and death for all the Korean people and approaches it very cautiously," said Lim Chae-jung, a spokesman for Mr Roh.

Mr Roh was elected as president last month promising continued engagement with the North, in contrast with the US' hawkish stance.

CRISIS CHRONOLOGY

16 Oct: N Korea acknowledges secret nuclear programme, US says 14 Nov: Oil shipments to N Korea halted 22 Dec: N Korea removes monitoring devices at Yongbyon nuclear plant 26 Dec: UN says 1,000 fuel rods have been moved to the plant 31 Dec: UN nuclear inspectors leave North Korea 31 Dec: N Korea threatens to pull out of NPT nuclear treaty

Timeline of tensions

He will formally take office in February, and is due to meet US President George W Bush shortly afterwards.

South Korea has already asked Beijing to try to persuade Pyongyang to calm the crisis over its nuclear programme.

South Korean officials later told Reuters news agency that China had agreed to use diplomacy to resolve the crisis.

South Korea also dispatched a senior official to Moscow - another ally of the North - on Friday.

Tensions over North Korea have increased since October, when the US said North Korea had admitted to having a separate, secret nuclear programme.

In December, Pyongyang said it had no choice but to reactivate its nuclear facilities at Yongbyon, 90 kilometres (60 miles) north of the capital, because the US was planning a pre-emptive strike.