Sixties fashion model turned novelist Sandra Howard also appears at the lit fest on June 23, interviewed by presenter Penny Smith about her book Ex-Wives.

The wife of Tory MP Michael Howard promises to give a sneak preview of her next novel, a “roman a clef” set between the 60s and the present day.

“In the 60s, my first husband wrote a book about Sinatra and we stayed with him and got to know the Kennedys.

“At the time I was modelling in New York. I was pretty young, 21,22 and pretty green. But not so green that I didn’t know how women were treated compared to how we are in the world today.”

It wasn’t, explains Howard, that she felt furious about that inequality.

“There wasn’t anything to compare it with. It was the norm. Men took advantage if they could.”

She recalls the modelling scene, especially in London was more relaxed, without the pressure to be “a size 0.”

“Famously there was a doctor in Harley Street who put people on a citrus fruits and protein diet so everyone walked around with barbecue chickens and oranges in their tote bags and the smell was pretty awful,” says Howard, whose own diet involved “a lot of boiled eggs”.

Ex-Wives, deals with young widow Kate who falls for an older divorcee with a troubled teenage daughter and a bi-polar ex-wife he still feels responsible for. She is also step-daughter to her mother’s shady new husband who turns out to have spy and drug connections.

“I was trying to imagine what it would be like to have lost someone at a young age, how much you would feel the guilt, as well as grief when you fell for someone else, and how it feels to be the woman who came after rather than the one who was left behind.”

Howard, whose books have been described as “less bonkers than Jilly Cooper, more fun than Joanna Trollope” tries to write about “people falling in love while making a bit of use of the great privilege of being married to a politician”.

She likes to include topicality, from home grown terrorism in A Matter of Loyalty, to a married mother dealing with high political office in Glass Houses.

“That book was the most political and was read as much by men as by women. It’s a pity when books get put in the category of being only for women but it’s sort of inevitable,” she says phlegmatically.

As for her other job, she says all politician’s wives have “Cherie Blair to thank for continuing to work while being the P.M’s wife”.

“Spouses of politicians are freer to do their own thing. Less expected to be everywhere in the constituency. That’s progress.”

Despite that, the watchword of any political spouse, nevermind the wife of the Home Secretary, must be discretion, both with insiders and outsiders.

“You put your foot in it at your peril,” she says chuckling.

“The biggest single concern is who you are talking to at a party, are they a journalist? But there’s always political rivalry with other politicians so you have to watch that too.”