Defying royal wishes, a British television channel said Tuesday it will show photographs taken immediately after the car crash that killed Princess Diana nearly 10 years ago.

Diana's sons, Prince William and Prince Harry, had protested that showing the images in a documentary scheduled to air Wednesday would be a "gross disrespect to their mother's memory" and "deeply distressing" to them.

"If it were your or my mother dying in that tunnel, would we want the scene broadcast to the nation?" the princes' private secretary, Jamie Lowther-Pinkerton, asked in a letter to Channel 4 that was released to the media.

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The documentary, titled "Diana: The Witness in the Tunnel," focuses on the role of the photographers at, before and after the crash that killed the princess, her friend Dodi Fayed, and their chauffeur in Paris on Aug. 31, 1997.

"We have weighed the Princes' concerns against the legitimate public interest we believe there is in the subject of this documentary and in the still photography it includes," said Julian Bellamy, head of Channel 4.

According to the company's Web site, the film poses questions such as "Did the photographers chase Diana to her death in the Pont d'Alma tunnel?" and "Were they too busy taking pictures to call the emergency services and did their presence hinder those services?"

Channel 4 has said it has dealt carefully with the photographs.

"We acknowledge that there is great public sensitivity surrounding pictures of the victims and these have not been included. Some photographs will be of the scene inside the tunnel but in none of the pictures is it possible to identify Diana or indeed any of the crash victims," it said.

"We do not show, nor have we ever considered showing, Diana's final moments."

Lowther-Pinkerton, however, said the photos "are redolent with the atmosphere and tragedy of the closing moments" of Diana's life.

"As such, they will cause the princes acute distress if they are shown to a public audience, not just for themselves, but also on their mother's behalf, in the sense of intruding upon the privacy and dignity of her last minutes," he wrote.

Lowther-Pinkerton's letter acknowledged that William and Harry had not seen the documentary, but the secretary had seen it and had briefed the princes on the contents.

Channel 4 said some of the photographs were taken by professionals and others by passers-by. The documentary also focuses on photographers who were arrested that night.

"In publishing the letter, the princes reluctantly feel that they have been left no choice but to make it clear publicly that they believe the broadcast of these photographs to be wholly inappropriate, deeply distressing to them and to the relatives of the others who died that night, and a gross disrespect to their mother's memory," said a statement issued by Clarence House, the official residence of the princes and their father, Prince Charles.

Channel 4 defended the documentary as "well-made and responsible."

"These photographs are an important and accurate eyewitness record of how events unfolded after the crash," it said.

French and British investigations into the crash have determined the chauffeur was drunk and trying to evade photographers. An inquest into Diana's death is set to begin in October after being mired in delays.

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