A leading Republican politician has been refused permission to challenge his guilty plea to charges of cruising in an airport toilet.

US Senator Larry Craig, 62, has pledged to serve out the rest of his term of office.

He was arrested on June 11th by an undercover police officer in a Minneapolis airport men’s room who said the senator had engaged in conduct “often used by persons communicating a desire to engage in sexual conduct.”

Minutes after he was arrested for lewd conduct, Craig denied soliciting for sex, saying “I’m not gay. I don’t do these kinds of things,” according to an audio tape released by police.

He denied that he had used foot and hand gestures to signal interest in a sexual encounter.

Despite a pledge to resign, he later announced he would challenge his guilty plea and claimed that he admitted to the charge in a panic to avoid triggering a story about his sexuality in his hometown newspaper.

However, Hennepin County District Judge Charles Porter has now ruled that the Senator’s guilty plea will stand.

“The defendant, a career politician with a college education, is of at least above-average intelligence,” Judge Porter wrote.

“He knew what he was saying, reading and signing.”

Minnesota case law requires a guilty plea to be “accurate, voluntary, and intelligent,” and Craig’s lawyers attempted to show that his panic at the idea that his bathroom arrest would become public means his plea was not intelligent.

The judge rejected this and pointed out the Senator waived his right to an attorney and discussed the charges against him with prosecutors.

News of Senator Craig’s guilty plea brought intense pressure on him from Senate Republican leaders and other colleagues in Washington to resign.

He first announced he intended to resign by September 30th, then said he was reconsidering.

He later said he would wait until after his appeal was heard.

Senator Craig announced yesterday that despite the court decision against him he will remain in the Senate until the end of his term – another 18 months.

He was a member of the House of Representatives before winning his first Senate term in 1990, and compiled a strongly conservative voting record.