Nureyev first met Jackie Kennedy after she watched him perform with Margot Fonteyn on his first tour of America with the Royal Ballet in 1963. Having applauded throughout 40-odd curtain calls until her hands were “black and blue pulp”, the first lady wanted to visit backstage but found herself blocked by Sol Hurok, the tour’s promoter, who was “fearful of the political repercussions” on future tours by Russian ballet companies if she met Nureyev. Her attempts to hold a supper party for the stars were also thwarted.

Mrs Kennedy was accustomed to getting her own way. Defying the furious Hurok, she ordered a private plane a few days later to bring the dancers to tea at the White House – where Nureyev cheerfully sat in the president’s rocking chair.

Good-naturedly accepting the fact that the White House was becoming “a sort of eating-place for artists”, Jack Kennedy received his wife’s visitors with his customary easy charm, although he would have been the first to admit a lack of enthusiasm for “all that cultural jazz”.

Nureyev, on the other hand, immediately appreciated Jackie’s knowledge of and passion for the arts, for antiques and excellence in general, and it was this encounter that marked the beginning of their lifelong friendship.

As Jackie Onassis, after the president’s assassination, she gave Nureyev financial advice. “The first real money he made was under Jackie’s influence,” said one of his intimates. “She’s the one who made him buy gold just before gold went up to thousands.”

And when in 1987 he returned to Russia for the first time to see his family and old friends, she got Senator Edward Kennedy to write to the Soviet ambassador in Washington expressing his “personal concern” that the trip “go smoothly”. It did.

Jackie’s London-based younger sister, Lee Radziwill, was also one of his most passionate admirers.

Lee was “a fantasy girl” whom many found a more intriguing personality than the relatively conventional Jackie.

Nureyev was adept at sharing himself equally between the two competitive sisters, photographed shopping on Fifth Avenue in New York with Jackie, dancing with Lee in Monte Carlo; but there was a time when he was very much closer to Lee – a bond she says her sister greatly envied.

She vows that she never had any delusions about Nureyev’s sexuality. He was “ninety-nine and a half per cent homosexual”; if a woman set her heart on him, she would “have to take the initiative”.

There are those who are convinced – “in the way that you just do know”, said one woman who knew Nureyev extremely well – that Lee succeeded in getting him into bed.

He even told a confidante that he had made her pregnant: “And what do you think she did? She destroyed my baby.”

Lee insists this is untrue. She does, however, admit to having been completely besotted by Nureyev. “I only ever wanted him to myself. Always.”

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