Six U.S. lawmakers hope to ease tensions with North Korea in the first visit by American officials since a crisis began last fall over the country's secret nuclear program.

They will tell North Korean officials that economic aid and trade lie ahead if Pyongyang abandons its nuclear program and improves relations with the United States, said the delegation leader, Rep. Curt Weldon (search), R-Pa.

"We are on a fact-finding mission to open doors for dialogue," Weldon said at Andrews Air Force base shortly before leaving Wednesday.

Weldon stressed that the lawmakers weren't traveling as Bush administration envoys and wouldn't negotiate. He said the administration neither encouraged nor tried to prevent the trip. On Tuesday, the lawmakers discussed North Korea with Assistant Secretary of State James Kelly (search).

"This is not an attempt to undermine or circumvent the president's message that the nuclear crisis can be resolved only through a multilateral effort," Weldon said earlier in an interview. North Korea wants one-on-one talks with the United States.

State Department spokesman Richard Boucher said the lawmakers were not carrying a message from the administration. "We, of course, look forward to hearing from them on their return," he said.

The lawmakers expected to arrive in Pyongyang on Friday and leave Sunday for South Korea. They expect to meet with North Korea's No. 2 leader, Kim Yong Nam, but were told they would not meet with top leader Kim Jong Il (search).

The talks represent a rare contact between the United States and isolated, impoverished North Korea. President Bush last year included North Korea in his axis of evil, along with Iraq and Iran.

Poor relations further deteriorated in October when North Korea, after being confronted by Kelly, admitted it had a clandestine, uranium-based nuclear program. U.S. officials believe North Korea already has one or two nuclear weapons and could develop more.

Washington said the program violated a 1994 agreement and cut off oil supplies promised under the accord. North Korea then announced it was reactivating an older plutonium program and expelled U.N. inspectors.

There has been little diplomatic contact. In January, North Korea's deputy U.N. ambassador, Han Song Ryol, met with New Mexico Gov. Bill Richardson, a former U.S. ambassador to the United Nations. North Korean diplomats met with U.S. officials in Beijing in April and demanded a long list of concessions in exchange for disarmament.

Weldon said he had planned the trip for more than a year, before the crisis developed. He has been in contact with Han and "the trip has been on and off 20 times," he said.

The No. 2 member of the House Armed Services Committee, Weldon is a maverick who has often stepped into tense diplomatic situations. He has been a frequent visitor to Russia, dating back to the Cold War, and wrote an influential plan to foster U.S.-Russian partnerships.

Weldon said he would tell North Korean officials about opportunities for energy projects and humanitarian assistance. But Weldon also said "there is a line drawn in the sand: Your nuclear program must end unequivocally."

A member of the delegation, Rep. Silvestre Reyes, D-Texas, said he hoped the visit would open a dialogue, "something besides a lot of the saber-rattling that's been pretty much the trademark of the administration."

Another Democrat on the trip, Rep. Eliot Engel of New York, said the visit could help break the impasse over whether negotiations should be bilateral or involve other nations.

He said if the congressional meeting is seen as bilateral, "perhaps that gives the North Koreans the hook to say that they have met with a U.S. delegation face-to-face with no other countries there, and then proceed to [multilateral talks]."

North Korea says the dispute is with the United States and talks should not involve other nations. The United States says North Korea is a regional problem and talks should involve countries that could be threatened by its nuclear program, such as South Korea and Japan.

The lawmakers expect to visit a school, a factory, a church and a computer center. They have also asked to visit North Korea's main nuclear complex at Yongbyon.

Other members of the delegation are Reps. Joe Wilson, R-S.C., Jeff Miller, R-Fla. and Solomon Ortiz, D-Texas.