WASHINGTON — Saddam Hussein’s intelligence agency secretly financed a trip to Iraq for three U.S. lawmakers during the run-up to the U.S.-led invasion, federal prosecutors said Wednesday.

The three anti-war Democrats made the trip in October 2002, while the Bush administration was trying to persuade Congress to authorize military action against Iraq. While traveling, they called for a diplomatic solution.

Prosecutors say that trip was arranged by Muthanna Al-Hanooti, a Michigan charity official, who was charged Wednesday with setting up the junket at the behest of Saddam’s regime. Iraqi intelligence officials allegedly paid for the trip through an intermediary and rewarded Al-Hanooti with 2 million barrels of Iraqi oil.

The lawmakers are not named in the indictment but the dates correspond to a trip by Democratic Reps. Mike Thompson of St. Helena, Jim McDermott of Washington state and David Bonior of Michigan. None was charged and Justice Department spokesman Dean Boyd said investigators “have no information whatsoever” any of them knew the trip was underwritten by Saddam.

Thompson released a statement Wednesday saying the trip was approved by the State Department.

“Obviously, had there been any question at all regarding the sponsor of the trip or the funding, I would not have participated,” he said.

In an interview Wednesday afternoon, Thompson said prosecutors have not suggested improper conduct by the members of Congress. The charity was investigated two years ago and was cleared to continue its work.

“The charity that paid for the trip, they didn’t do anything wrong,” said Thompson. “It was somebody involved with them that is alleged to have taken money inappropriately.”

As for his trip, Thompson said this week’s action do nothing to change what he witnessed.

“The people I saw in Baghdad, the people I talked to and the input I got from them certainly were not influenced by this charity or the donors to this charity,” he said.

“Obviously, we didn’t know it at the time,” McDermott spokesman Michael DeCesare said Wednesday. “The trip was to see the plight of the Iraqi children. That’s the only reason we went.”

Both McDermott and Thompson are popular among liberal voters in their reliably Democratic districts for their anti-war views. Bonior is no longer in Congress.

During the trip, the lawmakers expressed skepticism about the Bush administration’s claims that Saddam was stockpiling weapons of mass destruction. Though such weapons ultimately were never found, the lawmakers drew criticism for their trip at the time.

Oklahoma Sen. Don Nickles, then the second-ranking Senate Republican, said the Democrats “sound somewhat like spokespersons for the Iraqi government.”

Seattle-area conservatives dubbed McDermott “Baghdad Jim” for the Iraq trip.

Al-Hanooti was arrested Tuesday night while returning to the U.S. from the Middle East, where he was looking for a job, his attorney, James Thomas, said. Al-Hanooti pleaded not guilty Wednesday to charges of conspiracy to act as an unregistered agent of a foreign government, illegally purchasing Iraqi oil and lying to authorities. He was being held on $100,000 bail.

Between 1999 and 2006, he worked on and off as a public relations coordinator for Life for Relief and Development, a charity formed after the first Gulf War to fund humanitarian work in Iraq. FBI and Joint Terrorism Task Force agents raided the charity’s headquarters in 2006 but charged nobody and allowed the agency to continue operating.

McDermott identified that charity as the group financing the Iraq trip. In House disclosure forms, he put the cost at $5,510. Thompson also understood the charity to be financing the trip, spokeswoman Anne Warden said.

Prosecutors said Al-Hanooti was responsible for monitoring Congress for the Iraqi Intelligence Service. From 1999 to 2002, he allegedly provided Saddam’s government with a list of U.S. lawmakers he believed favored lifting economic sanctions against Iraq.

Thomas said Al-Hanooti would “vigorously defend” himself against the charges but he could not discuss the specifics of the case since he had seen none of the evidence.

Register staff contributed to this report.