The crisis sparked by North Korea's purported test of a nuclear device on Monday dominated a 70-minute press conference Bush held in the White House Rose Garden.

His appearance coincided with continued negotiations at UN headquarters in New York on a draft sanctions resolution targetting the isolated communist regime of Kim Jong-Il.

Bush said it had yet to be confirmed that Monday's blast was in fact a nuclear detonation. "But this claim itself constitutes a threat to international peace and stability," he said.

"We are working with partners in the region and in the United Nations Security Council to ensure there are serious repercussions for the regime in Pyongyang" as a result of the test, Bush said.

Bush said he had spoken with the leaders of the four other governments leading efforts to halt North Korea's nuclear effort -- Japan, China, South Korea and Russia, and had found unanimous agreement on the need for "a strong Security Council resolution that will require North Korea to abide by its international commitments to dismantle its nuclear programs".

He said the resolution "should specify a series of measures to prevent North Korea from exporting nuclear or missile technologies."

Washington also wants sanctions that would prevent "financial transactions or asset transfers that would help North Korea develop its nuclear missile capabilities," he said.

At the UN, US and Japanese diplomats were pressing a tough sanctions resolution while China, North Korea's closest ally and neighbor, sought to limit punitive measures for fear of bringing about the collapse of the fragile and poverty-stricken Pyongyang regime.

Acknowledging that his administration had often been criticised in the past for taking a "go it alone" approach to foreign policy, Bush said he was today fully committed to working diplomatically through the United Nations.

"That strategy did not work," he said of previous unilateral dealings with North Korea.

"I learned a lesson from that and decided that the best way to convince Kim Jong-Il to change his mind on the nuclear weapons program is to have others send the same message," Bush said.

"Our goals remain clear: peace and security in northeast Asia and a nuclear-free Korean peninsula," he said.

"We will work with the United Nations, we will support our allies in the region, and together we will ensure that North Korea understands the consequences if it continues down its current path," he said.

Bush went on to reiterate offers made in the context of six-nation negotiations last year to help North Korea with economic cooperation, trade and investment in exchange for it giving up nuclear weapons.

"I am saying as loud as I can and as clear as I can that there is a better way forward for North Korea," he said.

North Korea has asserted it needs nuclear weapons to defend itself from aggression by the United States, a possibility Pyongyang has repeatedly raised since the 2003 US-led invasion to oust Iraqi leader Saddam Hussein.

But Bush insisted in his press conference that Iraq was an entirely different situation and that his government had no plans for military action.

"I believe the commander-in-chief must try all diplomatic efforts before we commit our military," Bush said.

"Diplomacy hasn't run its course, and we'll continue working to give diplomacy a full opportunity to succeed," he said.

But the US president also said that in response to North Korea's "provocation, we will increase defense cooperation with our allies, including cooperation with ballistic missile defense to protect against North Korean aggression".

And he refused to rule out eventual military action if North Korea persists with its nuclear threat.

"I obviously look at all the options, all the time," he said.

US and SKorea fail to agree on paying for American troops
Seoul (AFP) Oct 11 - The United States and South Korea on Wednesday failed to agree on how to split the cost of stationing American troops in the country, amid rising regional tensions over North Korea's nuclear test.

"There has been almost no progress," a South Korean negotiator told the country's Yonhap news agency at the end of a two-day meeting, the fourth this year. "The two sides will set a schedule later for the next round."

The United States has 29,500 troops in the country, a legacy of the 1950-53 Korean War between US-led UN forces and northern communist troops that were backed by China.

No peace treaty was signed at the end of the conflict with North Korea, an isolated and impoverished regime that shocked the world on Monday by saying it had conducted an underground nuclear test.

In their negotiations on financing the US troop presence, both Washington and Seoul have argued that the other side should pay more.

The United States claims a South Korean offer of 710 million dollars per year constitutes just 38 percent of the total.

South Korea says it already pays over 40 percent when costs such as land leases and supplying South Korean troops to the US deployment are factored in.

"We will continue our efforts to end the negotiations within this year," the South Korean diplomat told the Yonhap news agency.

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