The US is rallying the international community to take action against North Korea following Pyongyang's announcement that it had detonated its first nuclear device in a test site in a northern province of the country.
US President George W. Bush, speaking at the White House early Monday morning, called the North Korean nuclear test a "provocative act" and stressed the need for international cooperation to deal with the problem. At the same time, the US already began talks with its allies in the UN Security Council on passing a new resolution that will enable the UN to take action against North Korea following the nuclear test.
"Such a threat itself constitutes a threat to international peace and security. The United States condemns this provocative act," Bush told reporters at the White House.
The US launched an immediate diplomatic effort in an attempt to provide a quick reaction to the North Korean nuclear test. Bush spoke by phone to leaders of Japan, South Korea, China and Russia, which are all members of the six-party talks the US has been conducting with North Korea for several years.
The main goal of US diplomacy at present is to put in place sanctions against the Pyongyang government. Russia and China are seen as the main players in any decision on sanctions, since they are among the few nations worldwide that have active trade and economic relations with North Korea. The US would also like to see South Korea, which is trying to open up to its neighbor from the north, apply pressure as well to signal to North Korea that becoming a nuclear power will isolate the country even more.
The US stressed that it is focusing now on diplomatic means to deal with the North Korean problem. US Ambassador to the UN John Bolton began work with his Japanese counterpart on the language of a new UN resolution concerning North Korea's nuclear test under the clause in the UN Charter that also allows the use of military force as a last option.
Analysts in the US stressed Monday that the most serious threat posed by North Korea's declared nuclear test is not necessarily the fear that the country would actually use nuclear weapons against its neighbors, but rather that it would sell nuclear technology and devices to other countries and perhaps even to terror groups. Pyongyang has declared it would not trade in its nuclear know-how, but in the past it has provided missile technology to countries like Iran, Syria and Pakistan.
In his White House statement, Bush referred to the threat of nuclear proliferation, making it clear that the US would see itself threatened directly if North Korea passes on its nuclear capabilities to others.
"The transfer of nuclear weapons or material by North Korea to states or non-state entities would be considered a grave threat to the United States and we would hold North Korea fully accountable for consequences of such action," Bush said.
Other world leaders also condemned North Korea, with some calling for harsh and immediate sanctions from the UN Security Council.
China - a key North Korean ally - openly criticized Pyongyang and demanded that it return to disarmament talks. Japan urged quick Security Council action, backed by Britain, Germany, France, Australia and other nations.
During a telephone call Monday, Bush and Japanese Prime Minister Shinzo Abe agreed that the Security Council must take "decisive action" against North Korea over its reported nuclear weapons test.
But there were no calls for a military attack on the North's nuclear facilities.
South Korean President Roh Moo-hyun condemned the reported test, saying it would make it difficult for Seoul to maintain its engagement policy with its communist neighbor. Roh said Seoul would try to resolve the situation through dialogue, but his government reportedly delayed the planned delivery of 4,000 tons of cement to the North on Tuesday as emergency relief.
South Korea also raised its military's alert level, and its intelligence agency warned that Pyongyang could conduct more tests, the Yonhap news agency reported.
South Korea, which does not have nuclear weapons, has shared the world's most heavily armed border with North Korea since the 1950-1953 Korean War ended in a truce, without a peace treaty.
"China expresses its resolute opposition," China's Foreign Ministry said, adding that the North "defied the universal opposition of international society and flagrantly conducted the nuclear test."
Beijing is a longtime supporter of North Korea but also the host of international talks aimed at persuading the fellow communist country to give up its nuclear ambitions. Its strongly worded reaction to North Korea's nuclear test opens up the possibility of punitive measures against Pyongyang, which relies on Beijing for all of the oil it consumes.
Abe, in Seoul for a summit with Roh, called for "harsh measures" against Pyongyang and warned of the dawn of a "dangerous nuclear age."
"The development and possession of nuclear weapons by North Korea will in a major way transform the security environment in North Asia and we will be entering a new, dangerous nuclear age," he said.
Russian President Vladimir Putin condemned the move, the Interfax news agency reported, and the Foreign Ministry called in Pyongyang's ambassador to warn him the test could "provoke a nuclear arms race in northeast Asia."
"Enormous damage has been done to the process of nonproliferation of weapons of mass destruction in the world," Putin said, according to Interfax.
The Foreign Ministry demanded that Pyongyang rein in its nuclear program but urged restraint from all nations.
A Security Council resolution adopted in July after a series of North Korean missile launches imposed limited sanctions on North Korea and demanded that the country rejoin international nuclear talks.
Pyongyang immediately rejected the plea.
Mohammed ElBaradei, head of the UN's nuclear watchdog agency, expressed serious concern.
"The breaking of a de-facto global moratorium on nuclear explosive testing that has been in place for nearly a decade and the addition of a new state with nuclear weapon capacity is a clear setback to international commitments to move towards nuclear disarmament," he said in a statement issued by the International Atomic Energy Agency.
ElBaradei said a negotiated solution is needed and that "resumption of dialogue between all concerned parties is indispensable and urgent."
The European Union and NATO also condemned the reported test.
"It is a threat to world peace and security and will demand the strongest possible reaction from the international community," NATO Secretary General Jaap de Hoop Scheffer said in Brussels.
British Prime Minister Tony Blair criticized the North for defying the international community.
"I condemn this completely irresponsible act by the government of the DPRK," Blair said, referring to the North by the abbreviation of its official name, the Democratic People's Republic of Korea.
"The international community has repeatedly urged them to refrain from both missile testing and nuclear testing," he said. "This further act of defiance shows North Korea's disregard for the concerns of its neighbors and the wider international community."
Germany, France and Australia also condemned the move and called for immediate UN Security Council action.
"Today's nuclear test endangers peace and security in the region and beyond," German Foreign Minister Frank-Walter Steinmeier said in a statement. "The United Nations Security Council is now called on to counter this North Korean provocation with a determined reaction."
Australian Prime Minister John Howard said his government would push for "swift and effective action," including financial, trade and travel sanctions.
"But if the United Nations fails to act effectively against this outrage from North Korea, it will represent a further diminution of its authority," Howard said.
India and Pakistan, South Asian rivals whose nuclear arms race has concerned the world, too, said North Korea's reported test could destabilize northeast Asia.
"We are deeply concerned at the reported nuclear test... in violation of its international commitments, jeopardizing peace, stability and security on the Korean Peninsula and in the region," said India's Ministry of External Affairs.
AP contributed to this report.