BEIJING, Jan. 10 Kyodo - North Korea has shown its ''nuclear deterrent force'' to an unofficial U.S. mission that inspected a key North Korean nuclear complex, the (North) Korean Central News Agency (KCNA) reported Saturday quoting a Foreign Ministry spokesman.

''As everybody knows, the United States compelled the DPRK (North Korea) to build a nuclear deterrent. We showed this'' to the group, the spokesman was quoted as saying by the KCNA report, monitored in Beijing. DPRK stands for the Democratic People's Republic of Korea.

''The permission given by the DPRK to visit the facility was aimed to give Americans an opportunity to confirm the reality by themselves and ensure transparency as speculative reports and ambiguous information about the DPRK's nuclear activities are throwing hurdles in the way of settling the pending nuclear issue,'' the report quoted him as saying.

The spokesman also said that if the visit contributed to dispelling ambiguity over the country's nuclear activities, it would be a ''substantial foundation'' for resolving the nuclear issue between North Korea and the U.S. peacefully.

The spokesman, however, did not elaborate on precisely what the country displayed to the group as a nuclear deterrent force.

The five-member U.S. group completed a five-day visit to North Korea on Saturday after inspecting the country's Yongbyon nuclear complex and exchanging views on nuclear issues with senior North Korean officials.

John Lewis, a Stanford University professor emeritus and head of the group, told reporters upon his arrival in Beijing that the mission visited several locations, including Yongbyon.

He said mission members were able to visit all the locations they wanted to see and met with North Korean scientists, military officers, officials in charge of economic affairs, and diplomats.

The delegation will draft a report on the trip in several days and must inform the U.S. government because Washington allowed it to visit the North, he said.

Lewis and the four other members of the mission refused to give further details of their trip.

It was the first time that foreigners have seen the 5- and 20-megawatt reactors, located about 90 kilometers north of Pyongyang and believed to be the core of North Korea's nuclear arms program, since the North kicked out a team of international inspectors in late 2002 who had been monitoring a freeze on plant operations since 1994.

The five, including former U.S. presidential envoy Jack Pritchard and Sig Hecker, former director of the Los Alamos National Laboratory, do not represent the U.S. government but may influence a pending second round of six-nation talks on North Korea's nuclear program.

The other two members are Senate foreign policy aides -- Keith Luse, an aide to Senate Foreign Relations Committee Chairman Sen. Richard Lugar, a Republican, and Frank Jannuzi, an aide to Sen. Joseph Biden, the committee's senior Democrat.

The group visited North Korea on invitation from the highest level of the North Korean government, according to a source in Beijing who follows North Korean issues.

The group's visit coincided with North Korea's declaration Tuesday that it is prepared to make a ''bold concession,'' suspending testing and production of nuclear weapons and abiding by a freeze of its nuclear facilities if the U.S. takes a series of steps, such as lifting sanctions.

The U.S. has said it wants North Korea to dismantle its nuclear program in a verifiable manner, not just freeze it, after which the U.S. would be willing to find ways to improve relations as part of a ''bold initiative.''

The two Koreas, the U.S., China, Japan and Russia held the first round in Beijing last August to seek a solution to the nuclear dispute, but failed to set a date or venue for the next round.

The latest nuclear impasse occurred in October 2002 when the U.S. said the North had admitted to running a uranium-enrichment program for use in nuclear weapons, violating a 1994 bilateral nuclear accord. ==Kyodo