Prince Harry had "no sudden outpouring of grief" when he was told his mother had died.
The 32-year-old royal has spoken out for the first time about how he felt when his father Prince Charles sat him down and told him Princess Diana had passed away after a car crash in Paris 20 years ago, and admits he was in "disbelief" at hearing the horrific news.
He said: "One of the hardest things for a parent to have to do is to tell your children that your other parent has died.
"But he was there for us, he was the one out of two left and he tried to do his best and to make sure we were protected and looked after.
"But, you know, he was going through the same grieving process as well."
Harry's brother Prince William felt "disorientated, dizzy and very confused" upon being told about his mother's passing.
He said: "I remember just feeling completely numb. And you keep asking yourself, 'Why me?' all the time. 'What have I done?' "
The last time Harry spoke to his mother was in August 1997 when they were on holiday at Balmoral, Queen Elizabeth's Scottish residence, and the flame-haired royal has admitted all he wanted to do at the time was run off and "play", something he has regretted ever since.
Speaking on upcoming BBC documentary 'Diana, 7 Days', which will air on Sunday (27.08.17), he said: "I think it was probably about teatime for us. And I was a typical young kid running around playing games with my brother and cousins and being told, 'Mummy's on the phone, mummy's on the phone' and was like, 'Right, I just really want to play.'
"And if I had known that was the last time I was going to speak to her the conversation would have gone in a very different direction.
"And I had to live with that for the rest of my life, knowing that I was that 12-year-old boy wanting to get off the phone and wanting to go and run around and play games rather than speak to my mum."
The documentary will also feature interviews with Diana's sister, Lady Sarah McCorquodale, and former Prime Minister Tony Blair, in the lead up to the 20th anniversary of Diana's death on August 31st.