A US Republican senator who pleaded guilty to disorderly conduct after his arrest in a men's toilet has announced his resignation from the Senate.
Mr Craig said he should not have pleaded guilty without legal advice
Idaho Senator Larry Craig, 62, said at a news conference in Boise: "I apologise for what I have caused... I am deeply sorry."
Sen Craig said his resignation would take effect on 30 September.
Undercover police arrested Sen Craig while investigating lewd behaviour in men's toilets at a US airport in June.
Idaho governor CL "Butch" Otter is expected to appoint another Republican to replace Mr Craig.
Republican leaders announced on Wednesday that Sen Craig had agreed temporarily to stand down from three Senate committees.
Party officials also referred the matter to the Senate ethics committee.
Sen Craig has also resigned from the 2008 presidential campaign of Republican Mitt Romney.
On Tuesday, Sen Craig - a married father of three - denied any wrongdoing and insisted: "I am not gay. I never have been gay."
On Saturday he said it would be wrong to keep his post while "pursuing legal options".
The BBC's Jonathan Beale in Washington says Sen Craig in his resignation speech did not admit he had done anything wrong and made no mention of the incident.
Sen Craig has a conservative record in the Senate and has voted against gay rights and same-sex marriage legislation.
Earlier this week, Sen Craig said police had misconstrued his actions at Minneapolis-St Paul airport.
He said he had pleaded guilty to handle the matter "quickly and expeditiously" but should not have done so without taking legal advice.
According to a police report, Sen Craig entered a cubicle next to the undercover policeman and tapped his foot in a way that the officer recognised as a sign of "a desire to engage in sexual conduct".
Sen Craig then gestured under the cubicle divider, at which point the police officer identified himself and arrested him.