SEOUL: North Korea needs to conduct a test to see if the vast sums it spent to develop atomic weapons have produced a working bomb, analysts say, but the political fall-out from such a blast could paralyse its already crippled economy. The nuclear card overwhelms all other cards the reclusive state possesses. Six-party talks aimed at ending its nuclear ambitions have been stalled for almost a year, but that did not stop Pyongyang from boasting in February it had nuclear weapons.

Recently, it has also stepped up activity at a site that could be used for an underground nuclear test, US newspapers reported citing US officials, spurring speculation that the North may be thinking of carrying out such a test. Washington warned the International Atomic Energy Agency that North Korea has been preparing to carry out an underground test since March and could set off a blast as early as June, Japan’s Kyodo news agency reported on Saturday citing diplomatic sources in Vienna.

If the North did go ahead, retribution would be swift and China, its last major ally, would be likely to waive its veto on the UN Security Council and join in punitive measures, a separate diplomatic source familiar with the workings of the United Nations said. “I think the Security Council will immediately seize on this issue. There will be no more sympathy for North Korea and no more money for North Korea,” the source said.

Beijing, the North’s main benefactor, would be the key player for any punitive measures. With its Security Council veto, any sanctions regime would be meaningless unless China enforced it along the border it shares with North Korea. The United States has acknowledged it might consider tougher action against Pyongyang, such as referring it to the Security Council, if it failed to return to the talks.

If the North did carry out a test, and China withheld its support, the Security Council would be likely to impose sanctions that could severely harm its meagre international commerce, the lifeblood of its faltering economy, analysts said.

The chief US negotiator to the six-party talks told a news conference in Seoul on Friday that there was great concern that North Korea would carry out a nuclear test, especially after its stunning announcement that it possessed atomic weapons.

“Often, when a country announces its membership in the nuclear club, the next step would be a test,” US Assistant Secretary of State Christopher Hill said after shuttling among Beijing, Seoul and Tokyo to meet leaders in a bid to restart the multilateral talks.

Analysts agreed that North Korea is considering a test.

“North Korea is probably tempted to conduct a nuclear test in order to turn up the heat a little more because nobody paid much attention when it said it had nuclear weapons,” said Baek Seung-joo, who leads studies on the North Korean military at South Korea’s Institute for Defence Analyses.

“But it is not going to be an easy move to make, because North Korea has to face a complete falling-out with China and the real possibility of UN sanctions,” he said.

Tension was heightened a few days ago when the head of the US Defense Intelligence Agency said North Korea might have mastered the technology for mounting a nuclear warhead on a missile capable of hitting the US West Coast.

THE FINAL STAGE: Pyongyang has also engaged in its first visible sign of bad behaviour, apart from the steady stream of hostile rhetoric, since the last round of stalled six-party talks in June 2004.

It has recently shut down its nuclear reactor, US and South Korean officials said. Proliferation experts say this would allow the North to harvest material that could be turned into plutonium bombs.

The North has already amassed enough fissile material from its nuclear programmes for six to eight bombs, the experts say.

It has two test options. An underground explosion would prove to the world that Pyongyang has a nuclear bomb, while detonation in the atmosphere would demonstrate the power of its nuclear devices and show its ability to strike with a nuclear weapon.

John Large, an independent British nuclear engineer who is familiar with the North’s nuclear programmes, said the reclusive state had already tested the triggering mechanism for a bomb and the only thing left to do was to set off a plutonium bomb to see if its technology works.

“Eventually you have to go to tests on the type of plutonium system the North has been developing. There is no supple or fancy computer simulation, or the absolutely certainty of a uranium weapon,” Large said in a telephone interview during a recent visit to Seoul to take part in symposium on nuclear threats in Asia.—Reuters