Princes William and Harry today strongly criticised the publication of a photo of their mother Diana, Princess of Wales as she lay dying in the wreckage of a Mercedes car.

The royal brothers said they were "deeply saddened that such a low has been reached", after Chi, an Italian weekly magazine, printed the image on its front page above the caption: 'l'Ultima Photo'.

Part of the Princess's face is seen in profile, her eyes closed, as a paramedic administers what appears to be a drip at the scene of the crash.

The Princes added that they would have been failing in their duty to her now if they did not make moves to protect her, as she once did for them.

Printing photos of the dying Princess, taken by the paparazzi photographers who were following her car when it crashed in a Paris road tunnel in August 1997, has until now been one of the last taboos in reporting a legacy that has been picked over in countless acres of newsprint.

Chi used the photo to promote an article about a new book about Diana, which is expected to incorporate a number of photos of the dying Princess. Lady Diana: The Criminal Investigation, by Jean-Michel Caradec’h, a French crime writer, also includes autopsy diagrams charting the injuries the Princess suffered.

Umberto Brindani, Chi magazine's editor, claimed that the image he chose for the front cover was "touching" and "tender".

When asked if Princes William and Harry might not find the photo offensive, Mr Brindani said: "On the contrary, I think they are the two people above all who want to know the truth."

He added: "She is not dead in the picture but looks as if she is a sleeping Princess."

But the Princes say in their statement: "Following this week’s publication in an Italian magazine of material relating directly to the death of our mother, we feel deeply saddened that such a low has been reached.

"Despite the support shown to us and our mother’s memory by so many people over the last eight years, we feel that as her sons we would be failing in our duty to her now if we did not protect her as she once did us.

"Therefore we appeal to all forms of media throughout the world to appreciate fully that publishing such material causes great hurt to us, our father, our mother’s family and all those who so loved and respected her."

The princes are not the first to criticise his decision to print the picture. Mohamed al Fayed, the Harrods chairman whose son Dodi also died in the car crash, said: "This heartless pursuit of money brings shame on those responsible for producing such a vile publication.

"It makes me sad and angry that a magazine would reproduce an image of the Princess as she clung desperately to life.

"The editor and the author, who probably have families of their own, have no thought for the feelings of those who loved the Princess, first and foremost her sons, the Princes William and Harry."

Joan Berry, 62, joint secretary of the Diana Circle UK, said she thought those involved in taking the photo, and publishing it, were "scum".

Terry Hutt, 71, from Cambridgeshire, a royalist who met Diana on numerous occasions through his work with disabled and homeless people, said he was "sickened" at the thought of the photo.

Mr Brindani said: "I published the picture for a very simple reason - it has never been seen before.

"In my opinion it is not a picture which is offensive to the memory of Princess Diana. As a thorough and informative news magazine we have merely reported the publication of a book in France regarding Princess Diana’s death.

"We carried an interview with the author and were provided material from a dossier which he acquired. The material from this dossier is in the book and includes the photograph as well as other documents.

"We were the first magazine to publish them but I understand that others in Europe - France and Spain - will also publish shortly."

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