British tabloid newspapers opted not to publish paparazzi pictures of Prince William and his girlfriend Kate Middleton on Saturday after he complained they had been aggressively pursued by photographers.

William, second in line to the throne, said that paparazzi had chased the couple on motorbikes and in cars as they were driven away from a London nightclub, just days after an inquest opened into his mother’s death in a high-speed crash.

Princess Diana and her lover Dodi al-Fayed were killed when their Mercedes limousine crashed in a Paris tunnel in 1997 while being chased by paparazzi.

“Having already been photographed leaving a club, he and Kate Middleton were then pursued in his car by photographers on motorcycles, in vehicles and on foot,” the prince’s press secretary Paddy Harverson said in a statement.

“This aggressive pursuit was potentially dangerous, and worrying for them. It seems incomprehensible, particularly at this time, that this behavior is still going on.”

The private secretary to Prince William and Prince Harry wrote to Channel 4 saying that they felt the images would be a “gross disrespect” to their mother’s memory.

Royal sources indicated that the letter had been written at the instigation of Prince William, who wanted to “take a stand” against intrusions into his mother’s dignity.

Politicians waded into the latest row to engulf Channel 4, with the Conservatives calling on the broadcaster to respect the princes’ wishes.

But Channel 4 said that it would screen the photos, which show the dying princess receiving medical assistance.

The identity of the car’s occupants is obscured.

Channel 4 declined a request from Clarence House to send a copy of the documentary, Diana: The Witnesses in The Tunnel, for the princes to view.

The film exonerates paparazzi from blame over the 1997 crash in Paris that killed the princess, 36, Dodi Fayed, 42, and the driver, Henri Paul.

A screening was held for Paddy Harverson, the princes’ press secretary, and Jamie Lowther-Pinkerton, their private secretary.

Afterwards, Mr Lowther-Pinkerton wrote to Hamish Mykura, head of history, science and religion at Channel 4.

The letter asked: “If it were your or my mother dying in that tunnel, would we want the scene broadcast to the nation? Indeed, would the nation so want it?”

The letter called on Channel 4 to remove from the program images of the car with the princess inside and of a medic treating her.

“These photographs, regardless of the fact that they do not actually show the princess’s features, are redolent with the atmosphere and tragedy of the closing moments of her life,” Mr Lowther-Pinkerton wrote.

Clarence House released the letter after Channel 4 failed to respond by a Monday deadline laid down by royal aides.

Kevin Lygo, Channel 4 director of television, rejected the demand. The princes were asking him to pull the documentary – an action he said would set a “dangerous precedent”.

Opposition culture spokesman Hugo Swire said: “Clarence House have now seen the footage, and believe it to be intruding upon the privacy and dignity of Diana’s last moments. Channel 4 would be crossing the line if they chose to press ahead.”

Jo Dyer graduated from the elite Sandhurst military academy alongside William in December, in front of his grandmother Queen Elizabeth II.

The army second lieutenant was killed by a roadside bomb attack west of the southern city of Basra, along with three colleagues and a local civilian interpreter.

“Prince William is deeply saddened to hear the tragic news of Jo Dyer’s death,” the 24-year-old’s Clarence House residence said.

“Jo was a close friend of his at Sandhurst and he is very much thinking of her family and friends right now and they will remain in his thoughts and prayers.”

Dyer was attached to the Second Battalion The Duke of Lancaster’s Regiment to gain operational experience in Iraq.

The deaths of Dyer and Private Eleanor Dlugsoz in Thursday’s attack brought to four the number of female British personnel killed since the start of the US-led invasion in March 2003.

Overall, 140 British troops have died since hostilities began.

Lieutenant Colonel Mark Kenyon, Dyer’s commanding officer, said: “Her contribution to our operations, even within a few short weeks, was invaluable.”

Prime Minister Tony Blair said Thursday the deaths were “as a result of a terrorist act.”

William, second in line to the British throne, is an officer in the Blues and Royals regiment of the Household Cavalry. The second lieutenant is known as Cornet Wales in the army.

William’s brother Prince Harry, 22, is preparing to serve in southern Iraq with the Blues and Royals.