Senior MP Crispin Blunt has been suspended by the Tories after being arrested on suspicion of rape and the possession of controlled substances.
The former minister, 63, identified himself as the man that Surrey Police detained in Horley on Wednesday morning, before his release on conditional bail.
The MP for Reigate said he will “co-operate fully” with the ongoing investigation and is “confident” that he will not be charged.
He said he has been interviewed twice over the incident, the first time three weeks ago when he “initially reported my concern over extortion”.
Conservative chief whip Simon Hart told Mr Blunt to stay away from Parliament during the process, the PA news agency understands.
After identifying himself, Mr Blunt had the whip suspended pending the outcome of the police investigation, meaning he is now an Independent.
Mr Blunt wrote on social media: “It has been reported that an MP was arrested yesterday in connection with an allegation of rape. I am confirming that MP was me.
“The arrest was unnecessary as I remain ready to co-operate fully with the investigation that I am confident will end without charge.
“I do not intend to say anything further on this matter until the police have completed their inquiries.”
He served in the Ministry of Justice as the minister responsible for prisons and probation between 2010 and 2012.
The police were unable to say if the controlled substances were drugs, as tests are being carried out.
The Tory Party has declined to comment on his arrest, first reported by The Sun.
Mr Blunt was first elected in 1997 and has said he does not intend to contend the next election.
Mike Clancy, general secretary of the Prospect union, which represents staff in Parliament, said: “How many more cases like this will it take for action to be taken to protect staff and visitors on the parliamentary estate?
“The Leader of the House must bring forward a vote on excluding MPs under investigation for violent and sexual offences from accessing the parliamentary estate as soon as Parliament returns.“
Mr Blunt is the latest in a string of sitting MPs to be arrested on allegations of sexual offences.
Back in May 2022, it emerged that a Tory MP in his 50s had been arrested on suspicion of indecent assault, sexual assault, rape, abuse of position of trust and misconduct in public office.
The Tory whips’ office said at the time that the MP had been asked not to “attend the Parliamentary estate while an investigation is ongoing”.
The latest extension to his bail is to mid-February.
One Conservative MP was arrested on suspicion of rape in 2020. He was never identified and police took no further action after an investigation.
On Thursday, a police spokesman said: “We can confirm a man was arrested yesterday morning in Horley on suspicion of rape and possession of controlled substances.
“He has been released on conditional police bail pending further inquiries.”