WASHINGTON (AP) — The Senate Ethics Committee said Wednesday that Idaho Sen. Larry Craig acted improperly in connection with a men’s room sex sting last year and had brought discredit on the Senate.

In a letter to the Republican senator, the ethics panel said Craig’s attempt to withdraw his guilty plea after his arrest at a Minneapolis airport was an effort to evade legal consequences of his own actions.

Craig’s actions constitute “improper conduct which has reflected discreditably on the Senate,” the letter said.

In an e-mailed statement, Craig told The Associated Press he disagreed with the ethics panel’s action.

“While I am disappointed and strongly disagree with the conclusions reached by the Senate Ethics Committee, from the outset I have encouraged the committee to act in a timely fashion and they have done so. I will continue to serve the people of Idaho,” he said.

The six members of the committee told Craig they believed he “committed the offense to which you pled guilty” and that “you entered your plea knowingly, voluntarily and intelligently.”

The panel said Craig only tried to remove his guilty plea after his attempts to avoid public disclosure had failed.

“Your claims to the court ... to the effect that your guilty plea resulted from improper pressure or coercion, or that you did not, as a legal matter, know what you were doing when you pled guilty do not appear credible,” the letter said.

The panel also said Craig should have received permission from the ethics panel before using campaign funds to pay his legal bills.

Craig, who is not running for re-election, has spent more than $213,000 in campaign money for legal expense and public relations work in the wake of his arrest and conviction last summer.

The committee said it had reached no conclusion about whether use of campaign funds was proper, but it said “it is clear that you never sought the committee’s approval, as required,” to use the money for legal expenses.

Any future use of campaign money for legal bills will be seen as “demonstrating your continuing disregard of ethics requirements,” the ethics committee wrote in its three-page letter.

The panel also admonished Craig for showing the arresting officer a business card that identified him as a U.S. senator. Craig has been reported to have told the officer at the time, “What do you think about that?”

The committee wrote, “You knew or should have known that a reasonable person in the position of the arresting officer could view your action and statement as an improper attempt by you to use your position and status ... to receive special and favorable treatment.”

Sen. Barbara Boxer, D-Calif., chairwoman of the ethics panel, declined to comment. A spokeswoman said the panel’s letter of admonition cannot be appealed.

The ethics panel took no further action against Craig.

Craig, a three-term Republican, pleaded guilty to disorderly conduct in August after he was accused of soliciting sex in a bathroom at the Minneapolis-St. Paul International Airport in June.

After the matter became public, Craig tried to withdraw his plea. A judge in Minnesota refused, saying Craig’s plea “was accurate, voluntary and intelligent, and ... supported by the evidence.” Craig has appealed that ruling to the Minnesota Court of Appeals.

Senate Republicans demanded the ethics investigation after news broke of Craig’s conviction last August. Craig first promised to resign Sept. 30, then reversed his decision. He now says he will stay in office until his term expires in January.

Craig has said an undercover police officer misinterpreted his foot and hand movements as signals that he wanted sex.

Craig, who lost several GOP leadership positions on Senate committees and subcommittees in the wake of the scandal, has been working with Boxer and other members of the Senate’s environment committee on a global warming bill and other matters.

Besides Boxer, the letter is signed by Sen. John Cornyn, R-Texas, the panel’s vice chairman, and Sens. Mark Pryor, D-Ark., Ken Salazar, D-Colo., Pat Roberts, R-Kan., and Johnny Isakson, R-Ga.

— Associated Press writer Erica Werner contributed to this report.