Princes William and Harry have spoken candidly about the death of their mother, Princess Diana, in an interview marking 20 years since she was killed in a car crash in Paris, paying tribute to the actions of their father in breaking the tragic news.

Excerpts of the BBC interviews released Wednesday mark something of a departure for the two princes, who have largely refrained from discussing Prince Charles's actions in other interviews describing their mother ahead of the anniversary. But in the documentary Diana, 7 Days, they appear to offer sympathy for him, quelling speculation that he had been uncaring in the crisis.

"One of the hardest things for a parent to have to do is to tell your children that your other parent has died," Harry said. "How you deal with that I don't know but, you know, he was there for us."

The documentary chronicles the week after the princess's death on Aug. 31, 1997 and features then-Prime Minister Tony Blair, senior royal aides and Diana's brother. The princes have spoken out for a series of programs and interviews in the run-up to the anniversary, sharing personal insights into their lives in keeping with their campaigns to promote mental health.

The two brothers discussed the funeral, with Prince William describing how he hid behind his bangs to keep out the prying eyes of sobbing crowds. He described the procession as a "very long, lonely walk," even though he understood there was a balance "between me being Prince William and having to do my bit, versus the private William who just wanted to go into a room and cry, who'd lost his mother."

FUNERAL DIANA/SONS, CHARLES, BROTHER

Prince William, right, seen beside Earl Spencer, Princess Diana's brother, with Prince Harry and Prince Charles behind them, talks in the new special about hiding his eyes behind his bangs during Diana's funeral. (AFP-Pool/Associated Press)

"I just remember hiding behind my fringe basically, at a time when I had a lot of hair, and my head's down a lot — so I'm hiding behind my fringe." William, who was 15 at the time, said "it was kind of like a tiny bit of safety blanket if you like. I know it sounds ridiculous, but at the time I felt if I looked at the floor and my hair came down over my face, no one could see me."

Sense of duty behind the casket

Prince Harry also talked about walking behind his mother's coffin in the funeral cortege, though he was only 12. Though he had previously told Newsweek magazine that this was not something any "child should be asked to do," he appeared in the program to suggest that in hindsight, he was glad to have taken part.

"I think it was a group decision, but before I knew it I found myself, you know, with a suit on, with a black tie, white shirt I think, and I was part of it," Prince Harry said. "Genuinely, I don't have an opinion whether that was right or wrong — I'm glad I was part of it. Looking back on it now, I'm very glad I was part of it."

Both said they wanted their mother to be proud of them. Prince William believed, though, that walking behind the cortege "goes to another level of duty."

"I just kept thinking about what she would want and that she'd be proud of Harry and I being able to go through it, effectively she was there with us, it felt like she was almost walking along beside us, to get us through it," he said.

Diana and her boyfriend, Dodi Fayed, died along with chauffeur Henri Paul when the Mercedes crashed in the French capital's Pont de l'Alma tunnel. An inquest in 2008 determined that the princess and her boyfriend were unlawfully killed, and that the driver and paparazzi pursuing her shared the blame for the deaths.

Britain Princess Diana

Prince William, left, and his brother, Prince Harry, have been speaking out about the death of their mother, Diana, Princess of Wales, as the anniversary of her death on Aug. 31, 1997, in a Paris car crash approaches. (Philippe Huguen/Pool Photo, File via AP)

In the documentary, Prince Harry described the role of the paparazzi as being one of the most difficult things to address.

"One of the hardest things to come to terms with is the people who chased her into the tunnel were the same people who were taking photographs of her while she was still dying on the back seat of the car," he told the BBC.

"And William and I know that, we've been told that numerous times by people that know that was the case. She'd 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."

The documentary Diana: Seven Days That Shook the World airs Sunday, Aug. 27, on CBC News Network starting at 10 p.m. ET/PT.