North Korea may stage a second nuclear weapons test to strengthen its hand during upcoming negotiations on scrapping its nuclear programme, South Korea's new defence minister warned on Friday.
Kim Jang-Soo, a former army chief of staff, ordered the 650,000-strong military to step up combat-readiness to deter possible aggression from the North, the defence ministry said.
"We have to be thoroughly prepared to counter the possibility of a second or third nuclear test by North Korea and a possible hostile act by it in the process of negotiations over its nuclear weapons programme," Kim said in a written order to his troops.
The six-nation nuclear talks are set to resume in Beijing on Monday, 13 months after the North walked out.
They involve the two Koreas, the United States, China, Japan and Russia.
The North staged its first nuclear test on October 9, sparking international condemnation and United Nations sanctions.
Later that month North Korean leader Kim Jong-Il told China that he had no plans for a second test but that increased international pressure could trigger "further measures".
Defence minister Kim issued his order after a closed-door meeting of 130 senior commanders, including General Kim Kwan-Jin, chairman of the Joint Chiefs of Staff, and the army, navy and air force chiefs of staff.
Foreign ministry spokesman Choo Kyu-Ho said he had no information about a possible second nuclear test.
He reiterated that Seoul will not recognise Pyongyang as a nuclear-armed state when the talks resume.
"Despite the nuclear test, we have not yet verified whether North Korea has nuclear devices that can be used as weapons," Choo told reporters.
He said it was unclear what the North's position would be after its missile tests in July and its nuclear detonation. But the next round, he said, should consider detailed ways of implementing a joint statement agreed at the six-party forum in September last year.
In that statement North Korea pledged to give up its nuclear ambitions in return for security guarantees, energy and other economic assistance and improved relations with the West.
But it pulled out of the talks two months later, protesting at US sanctions which froze its accounts in a Macau bank because of alleged counterfeiting and other illicit activities.
"The six-party talks should deal with specifics about implementing the September 19 joint statement and North Korea should also come on to this track," Choo said.
"We are coming to the talks with hopes that there should be some progress in terms of implementing the initial steps..."
South and North Korea have remained technically at war since the 1950-53 conflict and 29,500 US troops are based in the South.
The US forces want to consolidate 35 US bases scattered across the nation into two hub bases by 2008, including one at Pyeongtaek south of Seoul.
In addition to his warning about North Korea, defence minister Kim urged no further delay in the planned relocation of US bases to Pyeongtaek.
The defence ministry said this week that South Korea would not be able to complete the relocation by 2008 as scheduled, due to protests by residents and a dispute over cost-sharing.