SEOUL, May 23 (Yonhap) -- North Korea appears to have finished preparations and is "technically ready" to conduct a third nuclear test, a Seoul official said Wednesday.

   The remarks by the senior government official came a day after North Korea stepped up its bellicose rhetoric, vowing to boost its nuclear deterrent amid pressure from the United States, South Korea and Japan to refrain from carrying out a nuclear test.

   The North's foreign ministry spokesman said in a report carried by the official KNCA news agency on Tuesday that Pyongyang would take "countermeasures for self-defense" if Washington and Seoul continue to put pressure on the communist regime.

   "North Korea will make a decision on conducting a nuclear test based on its political judgment," the South Korean official told Yonhap News Agency by telephone.

   Major considerations for the political judgment would include "international pressure and sanctions as well as opposition from China and Russia," the official said on the condition of anonymity.

   South Korean military authorities have detected brisk activities at the North's northeastern nuclear test site of Punggye-ri, including new roads and structures, mining carts and excavation vehicles, the official said.

   In the English-language KCNA report, North Korea also said it "did not envisage such a military measure as a nuclear test" but the official said that the "claim is different from a technical judgment" by South Korea and the U.S.

   South Korean and U.S. intelligence authorities are closely watching activities at Punggye-ri, the official said.

   North Korea defied international warnings and launched a long-range rocket on April 13, although it fell apart shortly after take-off. Concerns have grown that the North may soon conduct a third nuclear test as its two previous rocket launches in 2006 and 2009 were followed by nuclear tests.

   Many analysts said the North's new nuclear test is just a matter of time following the unsuccessful attempt to launch a long-range rocket.

   On Monday, Glyn Davies, the U.S. special envoy for North Korea policy, warned that North Korea would risk more sanctions and deepening its isolation if it conducts a nuclear test.

   "It would be a serious miscalculation and mistake if North Korea worked to engage in a nuclear test," Davies said. "If there is a further provocation such as a nuclear test, there will be swift and sure reaction by the international community."

   kdh@yna.co.kr
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