The NIS said even if North Korea produced nuclear weapons they would be A-bombs to be dropped from aircraft similar to the one that devastated Hiroshima, Japan at the end of World War II, a committee member reported.

"The NIS said that because North Korea has yet to develop miniaturization technology, foreign news reports like those about North Korean exports of nuclear technology abroad, or reports that Pakistani nuclear scientist Abdul Qadeer Khan saw nuclear warheads atop missiles when he visited North Korea, were probably unreliable," another committee member said. Last year, the international press reported Khan as saying he saw missile-use nuclear warheads in North Korea.

The Defense Ministry said in its 2004 White Paper published Feb. 4 that North Korea could have manufactured one or two nuclear devices with about 10-14kg of plutonium the country extracted before IAEA inspections in 1992.

Evaluations of Pyongyang’s nuclear capabilities differ even within the government. Both the Defense Ministry and NIS are emphasizing the possibility that North Korea has manufactured atomic weapons, while the Unification and Foreign ministries are noncommittal citing lack of evidence.

During a parliamentary exchange Monday, Unification Ministry Chung Dong-young said the North Korean Foreign Ministry's nuclear declaration was merely a claim. While it is certain the North has 10-14kg of nuclear materials, it is uncertain whether Pyongyang has made nuclear weapons, he said.

Foreign Minister Ban Ki-moon told CNN on Sunday intelligence on North Korea's nuclear capabilities was being minutely analyzed and more observation was needed. Deputy Foreign Minister Lee Tae-shik, too, recently said it was a matter of interpretation whether North Korea's statement amounted to an official admission that the country really has nuclear weapons.

"Because there is no precise intelligence on North Korea's possession of nuclear weapons, there is confusion among government bodies,” Grand National Party lawmaker Kwon Young-se, who sits on the National Assembly's intelligence committee, said. “We need to form a special committee to get to the bottom of the issue."

An official with the Institute of Foreign Affairs and National Security said the different responses were attributable to the fact that the Foreign and Unification ministries must consider the country’s relationship with the North, while the Defense Ministry and NIS have to keep in mind battle capabilities. But he added, “Only if there is a common grasp of the situation is proper government policy possible."

(Yun Jeong-ho, jhyoon@chosun.com )