I was asked to cross out Sheridan's name from sex club visitors' book, says witness

Tony Cumberbirch, 53, said he was at the club with his wife, and they met a group of five people from Scotland.

He had not known who Sheridan was at that time, but he later saw the former MSP on television's Big Brother and recognised him.

Mr Cumberbirch told the High Court in Glasgow he remembered that particular night at Cupid's in Manchester because he had been asked by a friend to score out a name in the club's register.

The name had been Sheridan's, he alleged.

Sheridan accused Mr Cumberbirch of being a "proven liar", but the witness replied: "I have a criminal past. I'm telling the truth now, end of."

In 2004, the News of the World published allegations about Sheridan's private life, and he successfully sued the newspaper in 2006.

Sheridan, 46, and his wife, Gail, 46, are now on trial, charged with giving perjured evidence during the litigation. Both deny the offence.

One of the claims made against Sheridan has been that he visited Cupid's with two friends, Andrew McFarlane and Gary Clark, and two women, Katrine Trolle, a fellow Scottish Socialist Party member, and Anvar Khan, a News of the World columnist.

Mr Cumberbirch, of Manchester, said he and his wife, Louise, 35, had attended and also worked behind the bar at the club.

"It is a swingers' club … wife-swapping, liberated adults," he said.

The night he recalled was in 2002. He came to be in the company of a group of five people from Scotland.

"I know one now to be Tommy Sheridan. I did not know at the time," said Mr Cumberbirch, identifying Sheridan in the dock.

He was asked by the advocate-depute, Alex Prentice, QC, why he could recognise Sheridan now.

"Everything from Big Brother to this … it was not something I particularly watched but on this particular occasion I turned the television on and - Tommy Sheridan," he said.

Mr Cumberbirch also described the two women with the man he said was Sheridan.

He said he thought one was Scandinavian and the other was "dark-skinned and a little bit chunky".

Two witnesses, Anvar Khan and Katrine Trolle, have previously told the trial they went to Cupid's with Sheridan and a third, Gary Clark, said he had been to a club in Manchester.

He said he saw Sheridan again later at a party in Wigan, hosted by a friend called Ian, but had gone to bed early, saying: "It wasn't our sort of party.They weren't our sort of people."

But he said he had been "as close" to Sheridan at the party as he was now in the courtroom.

The trial also heard from Iain Campbell, the SSP's regional organiser for Fife.

He said Ms Trolle had told him at an SSP conference in 2006 that she had had an affair with Sheridan.

He told the court: "She said, and I was quite surprised, she said that she had an affair with Tommy Sheridan and this had been going on during the Perth conference in 2005."

Ms Trolle previously told the trial her affair with Sheridan had ended in 2004 and she had not been at the 2005 conference.

Paul McBride QC, representing Gail Sheridan, said: "They both can't be right."

The trial continues.