Liliane Bettencourt, the world's richest woman, announced yesterday that she would never see her daughter again as a family dispute over allegations that she had been abused by a photographer friend reached new depths.

Her comments were the latest chapter in a saga that has split one of France's wealthiest dynasties amid accusations of manipulation, jealousy and greed. They came after Françoise Bettencourt-Meyers filed a lawsuit which claimed that her 86-year-old mother — the heiress to L'Oréal, the cosmetics giant — had been exploited while in frail health.

An initial investigation has found that Mrs Bettencourt gave €993million (£925 million) in cheques, property, artworks and life insurance contracts to François-Marie Banier, a 61-year-old society photographer.

Mrs Bettencourt-Meyers, 55, took court action because she feared that her mother's fortune, estimated at $23 billion, could be frittered away following the death of André Bettencourt, her father, last year.

Mrs Bettencourt dismissed her daughter's claim as “very stupid”, as she defended her mental health in an interview with Le Journal du Dimanche.

“I find this whole affair completely idiotic. It's a waste of energy. It is very disagreeable and distressing,” she said. “It hurts me. I have known François-Marie Banier for 20 years, my husband knew him for 20 years. What's got into my daughter? Perhaps it's because I get on well with François-Marie Banier. Jealousy could play a part in this.”

Mrs Bettencourt went on: “I don't see my daughter any more and I don't want to see her.” She said her gifts to Mr Banier, which included paintings by Picasso, Mondrian and Matisse, were “not very big in proportion” to her wealth.

Mrs Bettencourt added that she had left her 27.5 per cent stake in L'Oréal — inherited from Eugène Schueller, her father, who founded the group in 1909 — to her daughter in bare ownership. “She will have it all after my death.”

She went on to talk about her relationship with Mr Banier, who counts Johnny Depp and Mick Jagger among his acquaintances.

“He's an artist and that motivates me,” she said. “We have extremely frank relations. He helped me a lot when I lost my husband.” In a letter to her daughter published by Le Monde, Mrs Bettencourt said: “It's thanks to him that I did not stay shut in the conventional environment to which I was destined because of my fortune.”

She denied reports that she was preparing to adopt Mr Banier: “I've never wanted to adopt a son, still less one who is more than 60.”

She rebuffed claims that Mr Banier had dominated and manipulated her. “Do you think someone can put me under his thumb just like that? I don't get the impression that he tried.” Mrs Bettencourt said she had been submitted to psychiatric tests at her daughter's request.

“I accepted willingly. I went to see a great psychiatrist, who told me: 'Everything's fine'.”

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