N. Korea Conducts 'Successful' Underground Nuclear Test

After North Korea launched its missile in April, China resisted moves by Japan, South Korea and the United States to use the United Nations as a vehicle for new sanctions against Pyongyang. The 2006 nuclear test, though, brought criticism from China and resulted in a regimen of new U.N. sanctions against North Korea.

The United States and Japan were taking the lead Monday in fashioning a diplomatic response that would condemn the latest nuclear test, according to a Security Council diplomat.

Secretary of State Hillary Rodham Clinton spoke in the morning with the foreign ministers of Japan and South Korea and will speak with her counterparts in China and Russia later in the day, State Department spokesman Ian Kelly said Monday. "In her conversations, the Secretary stressed the importance of a strong, unified approach to this threat to international peace and security," Kelly said in an e-mailed statement.

Last month, the U.N. Security Council imposed financial sanctions on three North Korean firms, marking the first time the United Nations has penalized individual companies linked to Pyongyang's nuclear- and ballistic-missile trade. The Security Council also reinforced a trade ban on items that North Korea could potentially use in the development of missiles.

The three state companies, Korea Mining Development Trading Corp., Tanchon Commercial Bank and Korea Ryongbong General Corp., have previously been sanctioned by the United States for trading missile technology with Iran, Yemen and Pakistan. Their customers included Abdul Qadeer Khan, a Pakistani physicist who is considered the father of his country's nuclear weapons program.

But North Korea has previously ignored demands by the 15-nation council to halt its nuclear weapon and ballistic missile programs.

North Korea instead has focused on establishing full diplomatic relations with the United States and receiving recognition as a nuclear state, according to several official statements and many analysts.

"North Korea's message is that they are heading towards status as a nuclear nation and that they will, therefore, deal only with the United States," said Cha Du-hyeogn, director of North Korean research at the Seoul-based Korean Institute of Defense Analysis, a government-affiliated think tank. "This is no easy situation for the United States and a worse one for South Korea."

Whatever North Korea's long-range negotiation goals may be, the immediate trigger for Monday's nuclear test appears to have been harsh criticism from the United States and most of the rest of world over the April long-range missile launch.

North Korean claimed the launch was a "peaceful" attempt to put a communication satellite in space. It said, too, that its satellite had gone into orbit and was broadcasting music that honored the leadership skills of Kim Jong Il.

The missile, though, splashed into the Pacific and sent nothing into orbit.

Still, it demonstrated to many Western experts a new and worrying capacity by North Korea to build multi-stage rockets that could one day deliver a nuclear warhead as far as Hawaii, Alaska or the U.S. mainland.

Staff writers Glenn Kessler in Washington and Colum Lynch at the United Nations and special correspondents Stella Kim in Seoul and Akiko Yamamoto in Tokyo contributed to this report.