Prince Harry has revealed he sought counselling after spending nearly 20 years “not thinking” about the death of his mother, Diana, Princess of Wales.

In an interview with the Daily Telegraph, he said it was not until his late 20s that he processed the grief – following two years of “total chaos”.

But he was in a “good place” because of the “process I have been through”.

The 32-year-old prince also said boxing “saved” him after he took it up as a “good way of letting out aggression”.

The Telegraph says Prince Harry had decided to talk about his past in the hope it will encourage people to break the stigma surrounding mental health issues.

Along with his brother and sister-in-law, the Duke and Duchess of Cambridge, he is promoting the Heads Together mental health campaign, the London Marathon’s charity of the year.

Speaking to the paper’s Bryony Gordon, Prince Harry said: “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.”

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

‘Head in the sand’

The Princess of Wales died in a car crash in Paris in August 1997.

Prince Harry said: “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 described himself as a “typical 20, 25, 28-year-old running around going ‘life is great’, or ‘life is fine’ and that was exactly it.

“And then [I] started to have a few conversations and actually all of a sudden, all of this grief that I have never processed started to come to the forefront and I was like, there is actually a lot of stuff here that I need to deal with.”

He said he decided to act after his brother, told him: “Look, you really need to deal with this. It is not normal to think that nothing has affected you.”

Asked whether he had seen a “shrink”, Prince Harry said: “I’ve done that a couple of times, more than a couple of times, but it’s great.”

But he said he could “safely say” his concerns were not related to his service as a soldier in Afghanistan.

On taking up boxing, Prince Harry told the paper: “Everyone was saying boxing is good for you and it’s a really good way of letting out aggression.

“And that really saved me because I was on the verge of punching someone.”

Prince Harry added: “Because of the process I have been through over the past two and a half years, I’ve now been able to take my work seriously, been able to take my private life seriously as well, and been able to put blood, sweat and tears into the things that really make a difference and things that I think will make a difference to everybody else.”