Hilary and Jackie, which had its European premiere in London on Wednesday night, is a warts and all chronicle of the life of Ms du Pre, a young genius whose career and life was cut short by multiple sclerosis.

It portrays her affair with her brother-in-law, which her sister Hilary said she allowed to continue because of her sister's frail emotional state.

But the film, which is based on Hilary's own book, has been criticised by fellow musicians and by many critics who have seen it.

Private Eye editor Ian Hislop, who has seen the film, says: "You can't just trust family recollection"

Ian Hislop, editor of Private Eye, said the trouble was that Ms du Pre was not alive to defend herself and he said her sister's account could not be trusted.

Another critic said too many scenes were derivative of the Oscar-winning movie Shine.

A planned demonstration outside the Barbican on Wednesday petered out with only two protesters - Royal College of Music students Jo Shouler and Wen-Jeng Chen - turning up.

Leading musicians join the fray

Until now the film's chief critic has been musician Julian Lloyd-Webber who has condemned it as a "disgrace" to Jackie's memory. But five other leading musicians joined him this week by writing a letter of protest to The Times.

Lord Menuhin, Itzhak Perlman, William Pleeth, Mstislav Rostropovich and Pinchus Zukerman all knew and worked with Ms du Pre.

They wrote: "This is not the Jacqueline du Pre that we, as her friends and colleagues, knew."

Family problems

The film has also caused a rift between Jackie's sister Hilary and her daughter Clare Finzi.

Ms Finzi said: "My mother now relates totally to the film. Her memory has become the film, and she cannot tolerate having me in the house because she cannot bear any other perspective."

"To say Jacqueline was the sole protagonist in this affair is simply untrue. It has been totally taken out of the context of my father's later affairs. "I think it is just impermissible to represent someone like that, especially when they are no longer around to fight their corner," she said.

Actress speaks out

But the star of the film, Emily Watson - nominated for a Golden Globe for her performance as the cellist - has hit back at the film's critics.

"I get upset when people imply that I don't have a huge amount of love and respect for Jacqueline du Pre, because I do.

"Let's not pretend that artists aren't sometimes messy people," she added.

"To me, she was an artist who had an emotional force field that was without boundaries. When you have that it slips over the edge. It's not a film about blaming anybody for anything.

"People are talking about this film as though we have raked through somebody's dustbins."

The film is based on Hilary du Pre's recollections in her book A Genius In The Family. Both Hilary and her brother Piers attended the premiere.