Prince William Prince Harry
Prince William and Prince Harry have some regrets over their final call with their late mom, Princess Diana. Pictured: Royal princes attend the wedding ceremony of Pippa Middleton to James Matthews at St Mark’s Church in Englefield Green on May 20, 2017. Getty Images/Arthur Edwards

If Prince William and Prince Harry could turn back time, they would have made their final phone call with their late mom, Princess Diana, a little longer.

In a new ITV News documentary, Princes William and Harry recalled their last phone call with their mom. The two royals admitted that they have some regrets over their last conversation because they didn’t take enough time to talk with Princess Diana as they were more keen on playing with their cousins at the time.

READ: Prince William and Prince Harry will hold TV tribute for Princess Diana’s 20th death anniversary

“The very last memory I have is a phone call from Balmoral. At the time Harry and I were running around, minding our own business, playing with our cousins and having a very good time,” Prince William explained. “Harry and I were in a desperate 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. That phone call sticks in my mind quite heavily.”

Prince Harry has the same regrets as his brother. “My turn. Off I go. It was her speaking from Paris. 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,” he said.

Prince William admitted that he still remembered what his mom told him during the call. After a few hours following their conversation, Princess Diana died in a fatal car accident. Prince William was just 15, while Harry was 12 when the incident happened. Both royals were very disappointed with themselves for not cherishing their mother more during her final hours. They both admitted that had they known it was their final call, things would have turned out differently. “You know, there’s a lot of — there’s a lot of grief that still needs to be let out,” Harry said.

Aug. 31 marks the 20th death anniversary of Princess Diana, Us Weekly noted. The documentary that Prince Harry and Prince William arranged as a tribute to their mom will air on ITV on Monday, July 24 at 9 p.m. EDT. Aside from the royal siblings, a few close family members will be invited to talk about the late princess.

The documentary will feature the different projects Diana was involved in, including her works on HIV and landmines. Another tribute to air on BBC will focus on the fatal car crash that caused her untimely death.

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