It was the affair that set tongues wagging and left in turmoil the marriage of Julian Barnes, the author of Flaubert’s Parrot, to Pat Kavanagh, the doyenne of literary agents.

Now the woman at the centre of the controversy, Jeanette Winterson, the novelist, has spoken about her romance with Kavanagh, who died last week, and described her final, touching conversation with her former lover.

Almost 20 years after their relationship ended, Winterson revealed that she had made contact with Kavanagh in hospital after the agent was diagnosed with a brain tumour and had made plans to visit her before “fate” intervened.

Barnes was deeply upset when Winterson “outed” his wife and went public with the affair while promoting one of her previous books. However, he is thought to have been reconciled to a reunion between the two women.

“Pat was very pleased when I called her – of course she was; it was a frightening situation,” said Winterson, author of Oranges Are Not the Only Fruit, a semi-autobiographical novel about teenage lesbian passion.

“We did agree that I would come to see her. But sometimes fate overtakes you, so it was very sad and very quick. There was no romantic hand-clasping or trysts . . . just a very nice, gentle conversation on the telephone and it ended well.”

Winterson, 49, said she had been alerted to Kavanagh’s illness last month by Ruth Rendell, the crime writer, after the 68-year-old agent collapsed in the street.

A source said: “Although they split all those years ago, the sub-plot is that Pat never fell out of love with her [Winterson] – I think they both stayed in love. When Pat knew she was approaching the end, it was Jeanette she had to see.”

The affair between the two women started in the 1980s when Kavanagh was acting as Winterson’s agent. Kavanagh, who married Barnes in 1979, reportedly moved out of the marital home to live temporarily with her lover and even darned Winterson’s woolly socks.

The relationship ended in 1989 and was made public three years later when Winterson – who by then had ditched the services of an agent – briefly talked about it in a newspaper interview to promote her novel Written on the Body.

“There are many lovers in Written on the Body, and not all of them are Pat,” Winterson said at the time. “It’s well known that we had an affair, but that ended three years ago.”

This weekend Winterson insisted the novel was not based on the couple’s affair – instead pointing out that she had dedicated an earlier book, published in 1987, to Kavanagh, who was renowned for her elegance and formidable negotiating skills.

“The book I wrote for Pat was The Passion. It’s dedicated to her,” she said. “Of course I did a book for her. It was important – at that time I was very much in love with her . . . It’s no big deal. It was 21 years ago.”

Winterson said her dealings with Kavanagh had been “perfectly cordial” after their split. They saw each other “from time to time”, according to the author, who has homes in the Cotswolds and Spitalfields, east London.

Describing her last conversation with Kavanagh, who was being treated at the National Hospital for Neurology and Neurosurgery in London, Winterson said: “I was saying ‘I’m sorry’ and all the things you do say.

‘It’s a shock’ and ‘It’s terrible’ and ‘It will be all right’ – and you do think it will be all right, as I’m sure Julian thought too.”

Winterson said Barnes, 62, whose bestsellers include The History of the World in 10½ Chapters and Arthur & George, had been left heartbroken by his wife’s death. The couple had no children.

“Everyone thought she was going to have an operation [to remove the tumour] and that didn’t happen. And that’s why [her death] was painful for everyone, because a lot of people weren’t able to say goodbye.”

Winterson, who once presented a BBC programme about Virginia Woolf, starring Joely Richardson and Saffron Burrows, is not the only author who has wounded Barnes in the past.

In 1995, he spectacularly fell out with Martin Amis after Amis dismissed Kavanagh as his agent in favour of Andrew Wylie, an American.

Kavanagh was born in South Africa and originally had ambitions to become an actress. Blessed with good looks that led many to compare her to Katharine Hepburn, she secured a nonspeaking part in Under Milk Wood. “I never got paid, but I did get to snog Richard Burton,” she said.

After abandoning acting, she became a stalwart at Peters Fraser and Dunlop, a leading literary and talent agency. However, last year she was involved in a revolt against the company’s increasing commercialisation and helped to set up United Agents.

It was testament to her influence that her entire list of authors, who included Barnes, Rendell, Robert Harris, Margaret Drabble and Joanna Trollope, followed her.

Other agencies are now likely to try to lure some of her authors away, but the majority are likely to remain loyal to United. Drabble said yesterday she had no plans to move.

Additional reporting: Roger Waite and Helen Brooks

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