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Reports of a possible second North Korean atom bomb test jangled nerves as China indicated its readiness to endorse “punitive” UN action against the secretive regime in Pyongyang.
Officials in Japan, South Korea and the United States moved quickly to damp down speculation about another test, saying they had detected no seismic activity in the vicinity of North Korea.
Japanese NHK public television, quoting unidentified government officials, reported earlier that a tremor detected in North Korea could indicate a second nuclear detonation.
“We have detected no evidence of additional North Korean testing,” White House spokesman Blair Jones said, although Japanese Foreign Minister Taro Aso did not rule out the possibility of a second trial.
The scare highlighted global tensions since Pyongyang declared Monday that it had for the first time tested a nuclear weapon.
The announcement sparked worldwide condemnation and triggered emergency UN talks on how to tackle the threat posed by the impoverished Stalinist regime, with even China — Pyongyang's closest ally — joining in.
“I think there have to be some punitive actions but also these actions have to be appropriate,” China's UN ambassador Wang Guangya told reporters Tuesday in New York.
The key question is how far China and Russia, which hold veto power on the UN Security Council, will be willing to go in backing tough sanctions proposed by the United States and Japan and invoking Chapter VII of the UN Charter.
Chapter VII, invoked in cases “of threat to international peace and security,” authorizes harsh sanctions or, as a last resort, the use of force to ensure compliance with Security Council resolutions.
“We want to see some elements from Chapter VII,” Wang said.
US Ambassador John Bolton described Wang's comment as “significant”, but he also conceded: “We don't have complete agreement on this.”
Beijing is by far the biggest provider of aid and trade to the regime of North Korean leader Kim Jong-Il.
Envoys of the five veto-wielding members of the Security Council — Britain, China, France, Russia and the United States — plus Japan were to meet again Wednesday after speaking twice privately Tuesday to try to narrow differences.
Australian Prime Minister John Howard appealed for unity, saying the United Nations faced a crucial test of its ability to deal with crises.
“The options for the world are few, we have to be realistic about that. The best response of the world is to act in unison,” he said in Canberra.
“Even an outlaw rogue state such as North Korea ultimately will take some notice of the rest of the world, including countries like China, to whom North Korea has been so close over the years, if they speak with one voice.”
Washington has suggested measures such as international inspection of all cargo to and from North Korea, financial curbs targeting Pyongyang's nuclear and missile programmes, restrictions on exports of goods with military use and sales of luxury items.
Japan put forward even tougher measures such as bans on North Korean ships and aircraft from entering or landing in member state territories, as well as a ban on all North Korean products and travel by senior North Korean officials.
After raising questions over both the scale and nature of Monday's test, US intelligence analysts said they assume North Korea did detonate a nuclear explosion but have not determined why the blast was much weaker than expected, a US official said.
“A test that didn't quite play out as expected would certainly be one of the hypotheses,” the intelligence official said on condition of anonymity.
“The working assumption certainly is that it was a nuclear explosion,” the official added, with seismographic data gathered by the United States pointing to a blast with a yield of as low as 200 tonnes.
In Moscow, Russian Defence Minister Sergei Ivanov said Pyongyang was now a “de facto” ninth world nuclear power.
Before Monday's test by North Korea, seven countries — the United States, Russia, Britain, France, China, India and Pakistan — were avowed members of the nuclear club.
An eighth state, Israel, is widely presumed to have such weapons but has never officially admitted so.
North Korea argues it needs atomic weapons to deter attack from the United States, and a Pyongyang official threatened to fire a nuclear-tipped missile unless Washington made concessions in the standoff over its atomic programme.
“We hope the situation will be settled before an unhappy incident of us firing a nuclear missile occurs,” South Korea's Yonhap news agency quoted an unidentified North Korean official in Beijing as saying.
“The North Koreans are not confused about what would happen,” US Secretary of State Condoleezza Rice retorted, saying firing a missile “would not be good for North Korea's security.”
