SEOUL - South Korea said on Wednesday it will soon announce plans to curtail the North's suspected trade in illicit weapons after its neighbor raised tensions by vowing to quit talks and restart its nuclear arms plant.

An angry North Korea on Tuesday lashed out at a U.N. rebuke over its launching of a long-range rocket 10 days ago, saying it was an infringement on its sovereignty that left it no choice but to walk away from a six-country disarmament-for-aid deal.

The International Atomic Energy Agency (IAEA) has said its inspectors have also been ordered to leave North Korea. Market players have mostly shrugged off the latest moves by the prickly North, which has previously threatened to boycott the nuclear talks and kick out international nuclear inspectors.

In a move bound to ratchet up tensions, South Korea is poised to reveal in the next few days that it will join U.S.-led interception of shipments suspected of carrying parts or equipment for weapons of mass destruction. Pyongyang has said such an action would be considered a declaration of war.

The plan, called the Proliferation Security Initiative (PSI) and joined by 94 countries, would let South Korea stop and board North Korean ships sailing in its territorial waters when suspected of carrying arms or other illicit materials.

North Korea has used its military threat for years to gain global attention and squeeze concessions out of regional powers.

By making these moves early in the administration of new U.S. President Barack Obama, it has more cards to play during his presidency and forces him to make crucial decisions about how it will manage its relations with Pyongyang, analysts said.

(The Obama administration) cannot afford to ignore this, said Ken Boutin, a security expert at Deakin University's School of International and Political Studies in Australia.

North Koreans traditionally have been very confrontational in their foreign policy approach and have sought to generate leverage by staking out apparently uncompromising positions that they can later back down from when they are provided with suitable incentives, Boutin said in an email to Reuters.

U.S. Secretary of State Hillary Clinton criticized the expulsion of the U.N. nuclear inspectors as an unnecessary provocation but said Washington was ready to talk.

Obviously we hope that there will be an opportunity to discuss this not only with our partners and allies but also eventually with the North Koreans, Clinton said in Washington.

North Korea's expulsion of U.N. nuclear inspectors is a major reversal of steps it took in 2007 halting the operation of the Yongbyon nuclear complex and allowing the IAEA in to seal facilities there. The plant that makes arms-grade plutonium was being disabled under the nuclear deal among the two Koreas, China, Japan, Russia and the United States.


The U.N. Security Council on Monday condemned North's launch of a long-range rocket, declaring it was a violation of a U.N. resolution adopted in 2006 after the North's nuclear and missile tests and ordered the enforcement of existing sanctions.

The Japanese government, which led the move for U.N. punishment of the North for the rocket launch over its territory said the six-way nuclear talks were the best way forward.

Shipments of energy aid to the North have slowed since last year because of a dispute over how to verify the North's nuclear inventory under the six-way disarmament deal struck in 2005.

Experts said the North could have its plant that separates plutonium from spent fuel rods up and running again in as little as three months.

Announcements like this from North Korea are part of a familiar pattern of behavior and as such are not likely to be a destabilizing factor for regional economies, analysts said

China, the closest thing North Korea can claim as a major ally, has called for calm and restraint from all sides in the six-party talks while expressing hope that the negotiations it hosts would resume.

New U.N. measures may cause Beijing to curb trade in a few items but some analysts said it is likely to maintain its flow of energy, grains and other materials that prop up the North's broken-down economy.