Rachida Dati goes racing with Alain Delon

The former French justice minister Rachida Dati shrugged off her recent problems to attend the Prix de l'Arc de Triomphe at Longchamp on Sunday. And just to make sure heads turned, she arrived on the arm of her friend Alain Delon.

Dati, now a Brussels MEP, and the one-time French heartthrob actor were there to watch the Irish horse Sea The Stars, already the winner of the Derby and the 2,000 Guineas this summer, romp home in the French classic by two lengths.

This was not the first time Dati had been seen on Delon's arm but it was their first outing since the publication this month of a controversial book, In the Shadow of Rachida, by her brother, Jamil Dati.

Jamil, one of 11 siblings, claimed that his famous sister had "sullied' their Moroccan father by giving birth to a daughter, Zohra, out of wedlock.

Throughout her pregnancy and Zohra's birth this January, Dati has steadfastly refused to name the girl's father, leading to endless speculation as to his identity. Indeed, Alain Delon has been up their with the main suspects, among them French sports minister Bernard Laporte, former Spanish PM Jose Maria Aznar and, in the early days, even the President of France himself, Nicolas Sarkozy.

The most extraordinary claim in Jamal's book was that the scene of Dati striding out of the Paris hospital with Zohra in a baby sling, snapped by dozens of paparazzi, was staged: the sling was actually empty, Jamal claimed, and Zohra was taken out of the clinic by another exit to avoid being jostled by the paps.

Dati has made no secret of the fact that she is infuriated by the book. "I've definitively cut myself off from my brother since he started this project," she said recently.

Jamal's lawyer, Frederic Berna, has claimed that she made serious efforts to stop its publication. Barna says that before she was fired by Sarkozy from the Justice Ministry, she summoned him to her office and ordered him to give her the identity of both the publisher and Jamal's co-author.

Berna claims Dati told him: "I can do anything for you. If you need me you can always count on me." When Berna said he wasn't interested, Dati is said to have replied: "It's a catastrophe - he mustn't bring out a book like that before the European elections. My brother must understand it's very risky. You know, my brother has already been confined to a mental hospital. He might have to go back..."