Prince Harry has revealed that he came close to “a complete breakdown” on numerous occasions after repressing the death of his mother, in a remarkably frank interview with Telegraph columnist and mental health awareness campaigner, Bryony Gordon.

Harry, the fifth in line to the British throne, was on the cusp of becoming a teenager when his mother Princess Diana died in a car crash in Paris.

“I can safely say that losing my mum at the age of 12, and therefore shutting down all of my emotions for the last 20 years, has had a quite serious effect on not only my personal life but my work as well,” the 32-year-old royal tells Gordon, for the inaugural episode of her podcast Mad World.

“I have probably been very close to a complete breakdown on numerous occasions when all sorts of grief and sort of lies and misconceptions and everything are coming to you from every angle.”

Prince Harry says his initial reaction to his mother’s death was to block it out completely.

 "My way of dealing with it was sticking my head in the sand, refusing to ever think about my mum, because why would that help?” he explains.

"(I thought) it's only going to make you sad, it's not going to bring her back. So from an emotional side, I was like 'right, don't ever let your emotions be part of anything.'”

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Then, he recalls, “as a typical 20, 25, 28-year-old running around going ‘life is great’, or ‘life is fine’… all of a sudden, all of this grief that I have never processed started to come to the forefront”.

What follows, he says, was “two years of total chaos” where he was unable to explain or understand his feelings.

“I just couldn’t put my finger on it,” he says. “I just didn’t know what was wrong with me.”

In the candid half-hour chat with Gordon – conducted over a cup of tea at Kensington Palace – Harry says he began to experience “flight or flight” reactions during public engagements, without fully understanding why.

He started to talk about these issues with friends, but it was his brother, Prince William, who finally persuaded him to seek help.

“It’s all about timing. And for me personally, my brother, you know, bless him, he was a huge support to me,” says Harry. “He kept saying this is not right, this is not normal, you need to talk to [someone] about stuff, it’s OK.”

"Some of the best people or easiest people to speak to is a shrink or whoever - the Americans call them shrinks - someone you have never met before,” he added, noting that he had seen a counsellor on “more than a couple of times”.

“You sit down on the sofa and say 'listen, I don't actually need your advice. Can you just listen'. And you just let it all rip.”

The prince says he also took up boxing: “That really saved me because I was on the verge of punching someone”.

Prince Harry says he is now “in a good place” because of the “process I have been through”.

He agreed to the interview as part of the Heads Together mental health campaign, the London Marathon's charity of the year that he, along with the Duke and Duchess of Cambridge, is endorsing.

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He admits that the prospect of sitting down and talking about his experiences made him “a little nervous, a little tight in the chest” but he called for others suffering to do the same.

“I can’t encourage people enough to just have that conversation because you will be surprised firstly, how much support you get and secondly, how many people literally are longing for you to come out,” he says.

Gordon has written extensively about her battle with alcoholism, bulimia and obsessive compulsive disorder. She appeared at last year’s Stylist Live festival, where she discussed coming out the mental health closet.

Her new podcast, Mad World, will feature a series of interviews with high-profile guests talking about their mental health problems.

The journalist said she had no idea the prince would be so forthcoming about his own personal experience with grief, before she conducted the interview.

“I thought that he might perhaps talk obliquely about the importance of discussing mental health,” she says. “Instead, it was like having a cup of tea with a friend who had been through a particularly difficult time, and lived to tell the tale. He did so movingly and articulately.

“He has shown the world that talking about your problems is nothing to be ashamed of – that actually, it is something to be positively encouraged.” 

If you or someone you know is suffering from a mental health problem, seek help and support with Mind

Visit Bryony Gordon's London marathon fundraising page in aid of Heads Together here

Photos: Rex Features