N Korea touts nuclear prowess
Seoul - North Korea boasted of its nuclear prowess on Tuesday, a week after launching a deadly artillery attack on South Korea, as China came under fresh pressure to rein in its unpredictable ally.
State media in the North, which has already tested two atomic bombs made from plutonium, said "many thousands of centrifuges" are operating at a new uranium enrichment plant which it claims is for peaceful purposes.
The country first disclosed the new plant to US experts less than two weeks before its artillery assault, which killed two civilians and two marines on a South Korean island near the disputed Yellow Sea border.
Experts and senior US officials fear the plant could easily be configured to make weapons-grade uranium.
Analysts say the nuclear revelation and artillery raid appeared co-ordinated to pressure Washington and Seoul into resuming dialogue and aid, and possibly to bolster the credentials of the North's leader-in-waiting Kim Jong Un.
For a third day, the US and South Korean navies staged a show of strength far south of the border involving 11 ships, air power and 7 300 personnel.
Heightening risk of war
South Korea is separately strengthening artillery and troop numbers on frontline islands near the border.
The North's state media blasted the naval drill, saying it was provocative and heightened the risk of war.
"We have full deterrence to destroy our enemies at once," said cabinet newspaper Minju Chosun. "If the US and South Korean enemies dare to fire one shell in our territory and sea territory, they will have to pay for it."
China's refusal publicly to condemn its ally for the shelling - the first of a civilian area in the South since the 1950-53 war - has stirred anger in South Korea.
And its call for talks to end the crisis has so far received a dismissive response from the United States and its Japanese and South Korean allies.
Beijing on Sunday suggested emergency consultations between envoys to stalled six-nation talks on the North's nuclear disarmament.
China's proposal dismissed
The White House said such talks would amount to "PR activity" unless Pyongyang changes its behaviour.
"The North Koreans need to demonstrate a seriousness of purpose in ending their aggressive behaviour," spokesperson Robert Gibbs said on Monday.
US ambassador Susan Rice urged tighter enforcement of UN sanctions in response to the "outrageous" artillery attack. China should play a "responsible leadership role" in defusing the crisis, she said.
Japan's foreign minister also faulted China's proposal.
"It's unacceptable for us to hold six-party talks only because North Korea has gone amok," Seiji Maehara told the Wall Street Journal.
"We must first see some kind of sincere effort from North Korea, on its uranium enrichment programme and the latest incident."
'World's most belligerent group'
South Korean President Lee Myung-Bak, in a toughly worded speech on Monday, did not mention China's suggestion. But he said the North would not voluntarily mend its ways and promised to make it pay "a dear price" for any future attacks.
"We should recognise that (South Korea) is confronting the world's most belligerent group," he told a cabinet meeting on Tuesday.
The attack on Yeonpyeong Island, a garrison and fishing settlement, injured 18 people in addition to the four deaths. It destroyed 29 homes, partly destroyed five others and slightly damaged 80, Seoul officials said, promising generous compensation.
With the nuclear disclosure and the bombardment, the North's leaders "demonstrated their ability to create trouble more or less with impunity", North Korea expert Andrei Lankov wrote in a commentary.
They "also hinted that they are not going to remain quiet if their demands for the resumption of unilateral aid and assorted political concessions are not met".
Diplomatic efforts were continuing to ease the crisis.
Seoul's foreign ministry said its minister Kim Sung-Hwan would attend a Kazakhstan summit of the Organisation for Security and Co-operation in Europe on Wednesday and Thursday.
It said he was expected to meet US Secretary of State Hillary Clinton and Russian Foreign Minister Sergei Lavrov on the sidelines.
The ministry also said it was trying to arrange talks in Washington early next month between Kim, Clinton and Japan's Maehara, to forge a united response to the shelling and discuss China's proposal.