Jeremy Clarkson left his ex-wife "shaking" with shock after hitting her with a surprise injunction in 2010 to block her writing a book on relationships he feared would lift the lid on their mmarriage.

Alex Hall was married to the Top Gear star for a year but allegedly continued a 10-year-long affair with him after they divorced and he remarried.

She told the joint parliamentary committee on privacy and injunctions that she received a late-night injunction a week after discussing her plans to write a "witty self-help book" about marriage.

"I texted him asking him to give me a call so we could talk about the book. He rang me immediately and asked what it was about. I explained the nature of the book and about a week later there was an injunction on me," she said.

"He said, 'I won't have anyone writing anything about me, why should anyone write anything on me?' I had no idea what an injunction was."

After discussing the book, Hall received a late-night text message from an anonymous number informing her that she was subject to an injunction on the basis that Clarkson was claiming that what she was writing about was false. She said she was terrified.

"I looked at the email and there was a 20-page injunction waiting for me. I started to shake and I haven't stopped since."

The court order blocked Hall from writing about "sexual or intimate acts" as well as Clarkson's "relationship with others, his private thoughts and feelings, his health, or his financial affairs".

Clarkson eventually lifted the injunction, in October, branding it pointless as he could not simply "sit on it" and avoid trial.

Hall's lawyer, Charlotte Harris,said that this was "not a wise admission". It showed Clarkson abusing the injunction as an interim action before court, she said.

"If you are going to say that everything that [Hall] has said was false then you should be serious about letting it go on [to court]," she said.

Hall said that she made it clear that she had no intention of mentioning her affair with Clarkson in the book, and it was only through the resulting legal battle brought about by the injunction that it came out.

"There wasn't really a public interest thing," she said about her story. "The public would be interested in what I would say because I used to be married to Jeremy Clarkson.

"There's a lot of psychological issues and life tools that one has to build as a result. It is a sort of witty self-help book that I wanted to do.

"There wasn't going to be that much about him. There wasn't anything detrimental there that could harm his career. In fact, it was going to be quite nice and favourable.

"I think he didn't want any acknowledgement that he had an ex-wife. He was worried about his current wife, that I still had an association with him, which he had not made her aware of."

Hall claimed that she was traumatised by the amount of negative press she attracted. She said she was still planning to publish the book.