The Republican US Senator who pleaded guilty to disorderly conduct in a men’s toile has announced that he will resign from the Senate.

Idaho Senator Larry Craig, 62, told a news conference:”I apologise for what I have caused… I am deeply sorry.”

Craig said his resignation would be effective as on the 30th September 2007.

Craig pleaded guilty to disorderly conduct on Aug. 1, and while he has since said he did nothing wrong, the episode has roiled the Republican party and produced numerous calls for him to step down.

Republicans lost control of Congress in last November’s elections, partly due to scandals, and are trying to regroup in preparation for the next round of voting, this time with the presidency at stake, in late 2008.

Many conservatives, a significant base in the party, oppose homosexualtiy.

The resignation clears the way for C.L. “Butch” Otter, the Republican governor of the conservative western state of Idaho that Craig represents, to name a replacement who would serve until the end of Craig’s current term in 2009, according to party officials, who spoke on condition of anonymity because they were not authorized to discuss the matter publicly.

This would maintain the current balance between Republicans and Democrats in the Senate where Democrats are in control 51-49 including two independents who usually vote with them.

Craig has not made any public statements about his case since an appearance earlier this week in Boise, Idaho, the state he represents, in which he said he had done nothing wrong. “I am not gay. I never have been gay,” he added emphatically.

He said any additional comment would be posted on his official Web site, where the only reference to the incident as of Friday morning was a text of the statement he read before the television cameras.

Craig, 62, served in the House before winning his first Senate term in 1990, and compiled a strongly conservative voting record.

He was arrested on June 11 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 on Thursday.

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

The officer, Sgt. Dave Karsnia, accused the three-term senator of lying and grew exasperated with his denials.

“Embarrassing, embarrassing. No wonder why we’re going down the tubes,” Karsnia said, according to AP.

In the police interview, Craig, 62, never admitted doing anything wrong and said his actions had been misinterpreted.

However, Karsnia wrote in his report that the gestures were consistent with efforts to find a sexual partner in the men’s room.

Craig later pleaded guilty to a reduced charge of disorderly conduct, which he now calls a mistake.

More Republicans distanced themselves from Craig on Thursday. Sen. John Ensign, who chairs the Republicans’ senatorial campaign committee, which provides finances and other political necessities to candidates, stopped short of calling on him to resign but suggested strongly that he should.

“I wouldn’t put myself hopefully in that kind of position, but if I was in a position like that, that’s what I would do,” Ensign told The Associated Press. “He’s going to have to answer that for himself.”

The party’s Senate leadership had previously called for the ethics committee to investigate, and on Wednesday took the highly unusual measure of asking him to give up his seniority in committee positions. Craig complied.

Craig continues to deny that he is gay or bisexual despite the behaviour.