Did Peter Cook have an affair with Jackie Kennedy?

It would have to go down as one of the least likely pairings of the 20th century - cult anti-establishment comedian Peter Cook and glamorous socialite and US First Lady Jackie Kennedy. But it has now been suggested that the two may have had an affair.

The startling claim was made by playwright Alan Bennett in a BBC4 interview with Mark Lawson. In the show, to celebrate his 75th birthday, Bennett said: "I may be libelling her, but I think Peter had an affair with Jackie Kennedy. I have an image of her standing next to Peter stroking his arm in the dressing room and he certainly went to parties with her."

Although the pair were known to be friends none of Cook's circle has ever suggested that their relationship went further than that, until now.

Cook and Jackie Kennedy first met and struck up a rapport in the early 1960s when the Beyond the Fringe revue, which also featured Bennett, visited New York and Cook met the US President John F Kennedy and his wife.

When Cook returned to the US and set up the Establishment Club in New York later in the 1960s, after Kennedy's assassination, Jackie would regularly visit, according to Cook's first wife Wendy. "I think she found my husband rather attractive as did a lot of women," she said, however she rejected the idea that their relationship ever went beyond "flirtations".

In the 1970s Cook and his comedy partner Dudley Moore visited to the US with the 'Good Evening' revue and he once again renewed his friendship with Jackie, who was now married to Greek tycoon Aristotle Onassis. During that visit he was introduced to Jackie's sister Lee Radziwill and is said to have embarked on an affair with her.

Cook, who was married three times, died in 1995 aged 57. Jackie Onassis, who is also alleged to have had affairs with JFK's brother Bobby and Marlon Brando, died in 1994, aged 64.