Threats add new tension to Korean war of words

NORTH Korea has threatened military action against South Korean and US warships plying the waters near the Koreas' disputed maritime border, raising the possibility of a naval clash just days after the regime's underground nuclear test.

Pyongyang, reacting angrily to Seoul's decision to join an international programme to intercept ships suspected of aiding nuclear proliferation, called the move tantamount to a declaration of war.

"Now that the South Korean puppets were so ridiculous as to join in the said racket and dare declare a war against compatriots", North Korea is "compelled to take a decisive measure", the Committee for the Peaceful Reunification of Korea said in a statement.

The North Korean army called it a violation of the armistice the Koreas signed in 1953 to end their three-year war, and said it would no longer honour the treaty.

South Korea's military said it was prepared to "respond sternly" to any North Korean provocation.

North Korea's latest belligerence comes as the UN Security Council debates how to punish the regime for testing a nuclear bomb on Monday. Ambassadors from the five permanent council members – the United States, Russia, China, Britain and France – as well as Japan and South Korea were working out the details of a resolution.

The success of any sanctions would depend on how aggressively China, one of North Korea's only allies, implements them. "It's not going too far to say that China holds the keys on sanctions," said Kim Sung-han, international relations professor at Seoul's Korea University.

South Korea, had responded to the nuclear test by joining the Proliferation Security Initiative, a network of nations seeking to stop ships from transporting nuclear bomb materials.

Seoul previously resisted joining the PSI in favour of seeking reconciliation with Pyongyang, but pushed those efforts aside this week after the nuclear test in the north-east.

North Korea warned yesterday that any attempt to stop, board or inspect its ships would constitute a "grave violation".

The regime said it could no longer promise the safety of US and South Korean warships and civilian vessels in the waters near the western maritime border.

"They should bear in mind that the (North] has tremendous military muscle and its own method of strike able to conquer any targets in its vicinity at one stroke or hit the US on the raw, if necessary," the army said.

North Korea disputes the maritime border drawn by the UN at the end of the Korean War, and has demanded it be redrawn further south. It has used the border dispute to provoke naval skirmishes in 1999 and 2002. Yesterday, it promised "unimaginable and merciless punishment" for anyone challenging its ships.

The South Korean newspaper Chosun Ilbo said spy satellites detected signs of steam at the North's Yongbyon nuclear complex, indicating it may be reprocessing nuclear fuel.