A U.S. Congressional delegation met with Libyan leader Moammar al-Qaddafi (search) and visited a nuclear site Monday as they wrapped up a landmark trip both sides hoped would improve relations between the two countries.

"We discussed the hope that we will achieve normal relations soon," delegation leader, Republican Rep. Curt Weldon (search) of Pennsylvania, said after the meeting.

Weldon, who met for 30 minutes with al-Qaddafi after a two-hour meeting between the Libyan leader and the entire delegation, said the discussions were "very positive."

"The leader is doing the right thing," he said.

Democratic Rep. Solomon Ortiz (search) of Texas said al-Qaddafi made "no new pledges" during the meeting but that the delegation "complimented him for keeping up his program."

The delegation's visit comes amid improving U.S.-Libyan relations after decades of rancor.

Al-Qaddafi said in an Italian newspaper interview published Monday that American and Libyan intelligence agencies may have worked together in the fight against terrorism.

"There are groups that are working against all of us," al-Qaddafi told Rome's La Repubblica daily. "It could be that there has been cooperation between secret services, in particular regarding Libyan citizens who fought in Afghanistan."

Rep. Darrell Issa (search), a California Republican, said al-Qaddafi "expressed his regret that a quarter-century has passed of isolation between our countries."

"It's just the first step," Issa said of the meeting.

Before meeting with al-Qaddafi, the delegation donned white smocks and shoe coverings to tour a nuclear reactor just east of Tripoli that is used for scientific research. U.S. and British experts are preparing to dismantle other nuclear sites used in Libya's nuclear weapons programs, which al-Qaddafi recently renounced.

The lawmakers also toured the rubble of al-Qaddafi's house, which was bombed by the United States in 1986. The attacks killed 37 people, including al-Qaddafi's adopted daughter, in retaliation for the bombing of a German disco that killed a U.S. soldier and a Turkish woman.

The United States imposed sanctions that year, accusing Libya of supporting terrorist groups. Ten years later, America said it would penalize the U.S. partners of European companies that did significant business in Libya and Iran.

In recent years, al-Qaddafi tried to end his international isolation, and has made a startling turnaround in the past year. He admitted his country's involvement in the 1988 bombing of a Pan Am jetliner over Lockerbie, Scotland, (search) and agreed to pay $2.7 billion to the victims' families.

He also admitted he had tried to develop weapons of mass destruction — including a nuclear bomb — and invited U.N., American and British inspectors to inspect his weapons programs and dismantle them.

"I think clearly that al-Qaddafi is for real in that he has made this switch," Issa told The Associated Press. "He has been a person of abrupt changes throughout his career."

After Libya admitted in September its involvement in the Lockerbie bombing, the U.N. Security Council voted to lift its sanctions, but the United States was proceeding more cautiously. Still, the U.S. lawmakers indicated that barring any changes of heart, diplomatic ties could soon be restored.

Libya is also counting on a restoration of economic ties. The sanctions have cost Libya more than $30 billion in lost business. Investment is especially needed for an oil industry that once made the North African country of about 5 million people a regional power.

The delegation's arrival came on the heels of that of another American lawmaker. Representative Tom Lantos, a California Democrat, landed Saturday in the first visit by an elected U.S. official in 38 years. His office in Washington said he, too, met with the Libyan leader, although it released no details of the meeting.

The U.S. Navy jet that carried the Weldon-led delegation to Tripoli on Sunday was the first U.S. military aircraft to land in Libya in al-Qaddafi's 35-year tenure as the country's leader.

On Sunday, the delegation met with Libya's prime minister, foreign minister and a delegation from the People's Congress — the equivalent of a parliament. They also walked through a section of Tripoli and visited a farm owned by al-Qaddafi's son, Seif el-Islam, who is seen as a possible successor to his father.

In addition to Weldon, Issa and Ortiz, the delegation includes Louisiana Democrat Rodney Alexander and Republicans Candice Miller of Michigan, Mark Souder of Indiana and Elton Gallegly of California.

Democrat Steve Israel of New York planned to join the delegation in Kuwait, which the Americans left for later Monday en route to Iraq and Afghanistan.