USA today

The claim came as some U.S. intelligence analysts are becoming increasingly concerned that North Korea might have three, four or even six nuclear weapons instead of the one or two the CIA now estimates.

"The (North) successfully finished the reprocessing of some 8,000 spent fuel rods," a spokesman from Pyongyang's Foreign Ministry said in a statement carried by the North's official news agency KCNA. The spokesman was not named.

Accusing the United States of taking a "hostile policy" toward the North, the statement said North Korea "made a switchover in the use of plutonium churned out by reprocessing spent fuel rods in the direction (of) increasing its nuclear deterrent force."

When reprocessed with chemicals, the 8,000 rods can yield enough plutonium for North Korea to make five or six more nuclear weapons, according to experts.

North Korea has claimed before that it has completed reprocessing its pool of 8,000 spent rods, but Thursday's statement clarified for the first time that it was using plutonium yielded from the rods to make nuclear weapons.

U.S. and South Korean officials have been skeptical about the claims that the rods have been reprocessed.

The bombs also could mean that the Stalinist regime might part with one bomb, either in a test or by selling it, although a senior official and the main communist newspaper Rodong Sinmun said North Korea has pledged not to export its nuclear capability.

Vice Foreign Minister Choe Su Hon said the North is expanding its "nuclear deterrence" but wouldn't say how many weapons it has, China's official Xinhua News Agency reported Thursday.

"We (have) no intention of transferring any means of that nuclear deterrence to other countries," Choe was quoted as telling reporters in New York, where he was attending the U.N. General Assembly.

North Korea also said Thursday that when necessary, it will reprocess more spent fuel rods to be produced from the small reactor in its main nuclear complex in Yongbyon, 50 miles north of Pyongyang.

North Korea says it has restarted its frozen 5-megawatt reactor at Yongbyon after kicking out U.N. nuclear inspectors and quitting the Nuclear Nonproliferation Treaty in January. Experts say it would take a year of operation before the reactor can produce enough to make a new weapon.

North Korea tends to escalate its harsh rhetoric in attempts analysts say are aimed at extracting concessions in crucial negotiations.

Last month, several U.S. government officials told The Associated Press on condition of anonymity that intelligence analysts are debating the extent of North Korea's nuclear capability.

Among the issues is whether the North Koreans have refined their nuclear weapon designs so they are able to use less plutonium to make a working weapon. Some analysts presume the North Koreans have made steady advances and thus are able to use their existing stockpile of weapons-grade plutonium more efficiently, the officials said.

However, the CIA as an agency has not reached that conclusion. It is sticking with its unclassified estimate of one or two weapons, the officials said. Other U.S. estimates put the number at three or four; still others are floating five or six weapons as a possibility.

The United States and its allies are trying to persuade North Korea to give up its nuclear programs. North Korea says it will do so only if the United States signs a nonaggression treaty, provides economic aid and opens diplomatic ties.

The nuclear dispute flared last October when U.S. officials said North Korea admitted running a secret nuclear weapons program in violation of international agreements.

The United States and its allies suspended oil shipments to the North. North Korea in turn expelled U.N. nuclear inspectors, withdrew from the global nuclear arms-control treaty and said it was reactivating its main nuclear complex, frozen since 1994.

The United States, the two Koreas, China, Japan and Russia met in Beijing in August to try to defuse the crisis. The meeting ended without agreement on when to hold the next round, as Washington and Pyongyang differed widely over how to resolve the dispute.

North Korea has since said it was no longer interested in further talks.

South Korea Vice Unification Minister Cho Kun-shik suggested North Korea's move was a "tactic to boost its negotiating power" when the talks resume.