Details in Hansard, parliament's official account of proceedings, recorded that London police (MPS) had sent a letter on Wednesday to the Speaker of the House of Commons "relating to the arrest of Mark Pritchard," 48, who represents the Wrekin constituency in Shropshire, western England.

"I write to inform you that on 2nd December 2014, Mark Pritchard MP was arrested at 6.14 p.m. at Holborn Police Station in London by MPS officers," Sandra Looby, the commanding officer in parliament, said in the police letter.

"The matter is subject to further investigation and is sub judice at the present time."

Pritchard could not be reached at either his office in parliament or his constituency office. Reuters left messages seeking comment with both, and contacted Pritchard by email. The Conservative party declined to comment.

"We can confirm that a 48-year-old man voluntarily attended a north London police station on Tuesday, December 2, where he was arrested, following an allegation of rape in central London," London police said in statement.

"He has been bailed to a date in early January 2015 pending further inquiries."

No further details of the alleged offense were immediately available.