Paul Burrell claimed Princess Diana would have been "heartbroken" if she witnessed Prince Harry "tearing down his family".
The former butler to the late Princess discussed how Harry's mother would have wanted him to "live a quiet life".
"What he's doing now is going to make everything so much worse for him," he said of the Duke of Sussex - who has been opening up about his struggles in the royal family.
"Diana would be heartbroken it's come to this. Not only would she be devastated that Harry is cut off from his family, but she'd disapprove of him tearing down the royals."
"She'd want him to stop airing his dirty laundry, and to live a quiet, private life, focused on his children," he told Closer.
Prince Harry recently opened up about losing his mum when he was only 12 years old, and admitted he felt angry that the world cried over her when they never even met her.
He memorably walked behind his mum's coffin at her funeral with his brother Prince William and other members of the Royal Family.
Harry explained: "(I was) showing one-tenth of the emotion that everybody else was showing: This was my mum - you never even met her. I was so angry with what happened to her and that there was no justice, at all. Nothing came from that."
The 36-year-old also told Oprah Winfrey in the documentary The Me You Can't See that he used drugs and alcohol to help cope with his ailing mental health because of Diana's death.
He confessed that he was "trying to mask something".
Harry told Oprah: "I was willing to drink, I was willing to take drugs. I was willing to do the things that made me feel less like I was feeling.
"But I slowly became aware that, ok, I wasn't drinking Monday to Friday but I would probably drink a week's worth in one day on a Friday or a Saturday night.
"And I would find myself drinking not because I was enjoying it but because I was trying to mask something."
