Tiffany Melvin's south London flat

After the verdict Mr Richards issued a statement through his solicitor saying he wanted to address his political career with renewed enthusiasm.

"As you can imagine, my family and I have been under great strain over the past 10 months, and I am delighted this case is now behind me," said Mr Richards.

"It is also a matter of great regret to me that this whole business has reflected badly on the Conservative Party," he added.

A spokesman for the Conservative group in the National Assembly said: "We are obviously pleased that he's cleared his name of these allegations."

But the spokesman added: "The issue of whether he can re-enter the group is entirely separate from the court case.

"The conditions for him to re-enter the group were made clear to him months ago when the whip was withdrawn."

The trial heard Mr Richards was spending the night in the capital with his friend the Conservative MP Nigel Evans MP when he went into Richmond alone and met Miss Melvin and her 31-year-old sister Tiffani in the Victoria Inn pub.

The Victoria pub in Richmond

He admitted to the jury trying to chat them up and being less than "frank" in police interviews when first asked of his intentions with the women that night.

Following a meal in a nearby pizzeria the three went back to the flat where the alleged assault was said to have occurred.

Fantasies

Defending Baroness Ann Mallalieu QC said: "The events of that night provide a classic cautionary tale for a middle-aged man at a loose end in London."

"This is the very stuff of middle-aged fantasies and played out night after night in bars and restaurants up and down the country."

The prosecution alleged that Mr Richards, who had a previous conviction for violence when he was a student, was thrown out of the flat after making sexually offensive remarks towards the girls.

The trial took place at Kingston Crown Court

He was then said to have punched Cassandra in the face before throwing her into a parked car, breaking her arm.

Throughout the trial he denied using offensive language or attacking the girl.

He told the court he was both "shocked and embarrassed" at being arrested and worried the press would find out about the incident.

Fellow AM David Davies, a member of the Welsh Assembly, told the jury that he had never any doubts about his behaviour in any capacity whatsoever."

Following his acquittal, though, Welsh Conservative Party Chairman Henri Lloyd Davies said he would not brush matters under the carpet if a complaint was made against Mr Richards.

Mr Davies said that he could not and would not stop passing on a complaint if such a complaint were made.

"Some people feel that some of his conduct - which he admitted was foolish - might have brought the party into disrepute, but that would have to be considered at some length."