Photos of Princess Diana dying in a Paris tunnel would cause Prince William and Prince Harry "acute distress" if shown on TV, Clarence House has said today.
Channel 4 is due to broadcast a documentary on the death of Diana, The Witnesses in the Tunnel, tomorrow, in which controversial images of the August 31st 1997 crash are to be shown.
One of the photos shows the crashed car which Diana had been travelling in while she was still in the wreckage and another depicts a medic administering emergency treatment to the Princess of Wales in an ambulance.
The private secretary to the princes has written to the broadcaster asking them to remove the images from the documentary.
And in a highly unusual step by the royal household, after it received no response from Channel 4, the full letter from Jamie Lowther-Pinkerton has been published on the Clarence House website.
"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," a Clarence House statement read.
In the letter itself, Mr Lowther-Pinkerton thanks Channel 4 for allowing the royal household to see the documentary in advance.
He explains that he "verbally briefed" the princes on the content of the programme and that they asked him to "communicate to you in the strongest terms possible that their position remains unchanged" from the comments they made when the Italian magazine Chi published a photograph of the scene in July 2006.
On that occasion the princes said that publishing such material "causes great hurt to us, our father, our mother's family and all those who so loved and respected her".
Mr Lowther-Pinkerton goes on to question whether showing the images is a matter of public interest and calls on the broadcaster to respond with their position on the matter by 09:00 BST yesterday.
"These photographs, regardless of the fact that they do not actually show the princess' features, are redolent with the atmosphere and tragedy of the closing moments of her life," he writes.
"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 mothers behalf, in the sense of intruding upon the privacy and dignity of her last minutes."
In a statement, Channel 4 defended its position and reaffirmed its intention to broadcast the images in the documentary tomorrow.
"Channel 4 acknowledges the concerns expressed by the princes William and Harry about the documentary; we would like to make clear that it was not our intention in commissioning this programme to cause them distress and we do not believe the film is in any way disrespectful to the memory of Princess Diana," head of Channel 4 Julian Bellamy said.
"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.
"No images of the victims of the crash are shown in this film because we made a clear decision from the outset to uphold the consensus quite properly reached by the British media not to use any images that depict the occupants of the car after the crash. Those images that are included have been selected with due consideration for the feelings of the relatives of those involved."