"They've tested one. Therefore there's no reason to believe that at some time in the future, when it serves their purposes, that they won't test another one," he said.

"I suspect some day they will."

Bell heads 29,000 US troops in the peninsula, supporting South Korea's 680,000-strong armed forces against any attack from the North's 1.1 million military.

"Should North Korea attack the South in any way, the combined forces command will respond and we will win quickly and we will win decisively," he said.

"It's just that simple. Those are not hollow words, that is a fact."

A South Korean foreign ministry official said Friday that activity had been detected at Punggye in the northeast of North Korea, near the site of the first test, but there were no signs yet of preparations for a second detonation.

The official was speaking after US television network ABC reported that North Korea appeared to have prepared for a repeat blast. The first sparked worldwide concern and United Nations sanctions.

On Sunday Chung Hyung-Keun, a South Korean opposition lawmaker who was a deputy spy agency chief in the 1990s, said unusual personnel and construction activity had recently been detected at Punggye.

Chung said North Korea was fully prepared for a repeat test but was unlikely to go ahead pending the outcome of upcoming talks.

The latest round of six-nation talks on the North's nuclear programme ended in Beijing in December without a breakthrough. The US State Department has said the talks could resume as early as this month.

Financial officials from North Korea and the United States are scheduled to meet separately, possibly this month, to try to settle a row over US financial sanctions imposed over the North's alleged counterfeiting and other illegal activities.

earlier related report
China Cannot Confirm Quick Restart To North Korea Nuke Talks
Beijing (AFP) Jan 9 - China on Tuesday said it hoped for an "early resumption" of six-party talks on North Korea's nuclear program but would not confirm a US statement that they could restart in January. "An early resumption of the six-party talks is a common wish of all the six parties," foreign ministry spokeman Liu Jianchao told a press briefing.

"We hope all the parties can find ways to solve problems and strive for an early resumption of the talks and positive progress," added Liu, who said setting an actual date required further "consultations".

A US State Department spokesman said on Friday the talks could resume later this month after a fruitless previous round in December.

"I would expect that those talks could reconvene again as early as January, as early as this month," spokesman Sean McCormack said.

McCormack said the main US negotiator, Assistant Secretary of State Christopher Hill, was working to get the parties -- China, Japan, North and South Korea and Russia -- together within the next four weeks.

The long-running six-party negotiations were suspended in late 2005 after North Korea walked out in protest at US financial sanctions imposed on a Macau bank accused of illicit dealings on behalf of Pyongyang.

The talks resumed in December -- following North Korea's October nuclear weapons test -- but ended in deadlock after Pyongyang insisted the financial sanctions be lifted before it would discuss nuclear disarmament.

Asked what he thought of the prospects for the talks achieving progress in 2007, Liu said that disarming North Korea was an "arduous task" requiring the patience and wisdom of all parties.

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