Prince Harry pans paparazzi who took photos of Princess Diana as she died

Prince Harry has launched a scathing attack on paparazzi at the scene of his mother Princess Diana's death, saying they opted to take photos of her dying rather than help.

Ahead of new BBC documentary Diana, 7 Days - which marks 20 years since she was killed - the royal took aim at photographers at the scene, saying they profited from her death.

"One of the hardest things to come to terms with is the fact that the people who chased her into the tunnel were the same people who were taking photographs of her while she was still dying in the backseat of her car," he said in a teaser.

"William and I know that. We've been told that numerous times by people that know that was the case."

Harry has spoken before about the pain he suffered after his mother's death, opening up on how he and older brother William's last conversation with her was "desperately rushed".

But had paparazzi prioritised his mother's health rather than trying to get a lucrative snap, he said they might not have had such regrets.

"She had quite a severe head injury, but she was very much alive on the back seat. And those people that caused the accident, instead of helping, were taking photographs of her dying on the back seat.

"And then those photographs made their way back to news desks in this country."

In July, another documentary on Diana's life gave a painfully raw glimpse into the struggles she faced.

Diana, Our Mother: Her Life and Legacy showed how Diana fought for the rights of the homeless and AIDS sufferers, even as her marriage was crumbling.

Newshub.