De Villiers's autobiography, Politically Incorrect, co-written with journalist Gavin Rich, hits the shelves soon. In it the ex-Bok coach accuses Watson and ANC MP Cedric Frolick of being the instigators in the infamous sex tape scandal.

In September 2008, claims surfaced that De Villiers, a staunch Christian and a married father of two, had been caught on video having sex with a woman in a car. He denied the claims at the time.

In his book De Villiers, who last coached the Boks in their quarterfinal exit against Australia in the 2011 Rugby World Cup, claims Watson and Frolick orchestrated the scandal to "punish" him for not selecting Watson's son, Luke.

De Villiers wrote that he was approached by the late Chris Hewitt - then the SA Rugby Union's media manager - who told him of the existence of the tape and how Watson and Frolick were planning to release it publicly.

''By then Chris had already informed me that Cedric, who, as an ANC MP, was involved with the parliamentary portfolio committee on sport and recreation, had told him that he would rather have a white coach that would listen to him than a black coach who did his own thing.

"Chris had been the middleman between Cheeky and the politicians. He was the one who conveyed to me their unhappiness that I was not toeing the line," wrote De Villiers.

But Watson told the Sunday Times: ''I really have no comment to make, nothing whatsoever. No, I haven't read [the book], but I heard some whispers out there.

"But, you know, I don't reply to bald-faced lies, it's the only comment I'm willing to make."

Frolick said he was disappointed at the allegations.

''Mr De Villiers, in his discussions, never raised this issue with me ... I'm astounded that he was carrying this around with him.

"In fact, I should rather say, he didn't have the guts to raise this with me. I'm very, very disappointed," he said.

De Villiers wrote of the "conspiracy" against him: ''The way I see it, Cheeky and Cedric wanted me suspended, and if that was the plan - and I did only have Chris's word linking them to the tape - then it didn't work."

Wrote De Villiers: ''I will never feel the same way about Cheeky again, as I gave him my trust, which I feel he abused.

"That's why I don't have any respect left for him. When I bump into him now, I greet him, because I feel it is polite to do so, but I am not friendly with him. It's a real shame, because that's not how we're really supposed to live."

Hewitt died in a plane crash in 2008.