William And Harry Reveal Their Agony Over Last Phone Call With Mom Diana

Princes William and Prince Harry deeply regret that their last contact with their mom Diana before her tragic death nearly 20 years ago was a brief phone call.

In fact, William and Harry, who were just 15 and 12 at the time, admit they got off the phone quickly with their mother while in a rush to do other things.

Speaking on a new ITV documentary called "Diana, Our Mother: Her Life and Legacy," set to air in England and on HBO in the U.S. on Monday, William and Harry remember their final call with Diana just hours before her 1997 death in a car crash in Paris, as CNN reports.

The two brothers were at Balmoral Castle in Scotland when Diana called from Paris and Harry noted, "I can't necessarily remember what I said, but all I do remember is regretting for the rest of my life how short the phone call was."

Harry, now 32, whose relationship with Suits actress Meghan Markle,  35, has intrigued the world, said, "This is the first time that the two of us have ever spoken about her as continued, "If I'd known that that was the last time I was going to speak to my mother, the things I would have said to her. Looking back at it now -- it's incredibly hard. I have to deal with that for the rest of my life: not knowing that it was the last time I'd speak to my mum, how differently that conversation would have panned out if I'd had even the slightest inkling that her life was going to be taken that night."

Speaking in the documentary, Prince William said he and Harry had been "running around, minding our own business, playing with our cousins and having a very good time" and were in a rush to say "goodbye, see you later, can I go off?"

"If I'd known what was going to happen I wouldn't have been quite so blasé about it," the Duke of Cambridge said. "That phone call sticks in my mind quite heavily."

Their dad Prince Charles and Di were officially divorced in 1996. People around the world were devastated when Diana died in a car accident the following year in Paris. She was just 36. Charles married his longtime mistress Camilla Parker Bowles in 2005.

William, now 35, said of his late mom, "There's not many days that go by that I don't think of her. Her 20th anniversary year feels like a good time to ... remember, you know, all the good things about her and hopefully provide maybe a different side to her that others haven't seen before," he said.

Prince Harry recalled that Diana was a "kid through and through….all I can hear is her laugh in my head. And that sort of crazy laugh of where there was just pure happiness shown on her face."

William said, "We felt, you know, incredibly loved, Harry and I ... and I'm very grateful that that love still -- still feels there.

Princess Diana's tragic death on August 31, 1997 is being marked by a slew of TV specials. But perhaps the most poignant one will be British ITV's Monday documentary.

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