He said: “Harry really is going out of his way to make sure that there isn’t material in there [the book] that can be seen as negative towards the Queen or her reign in any way whatsoever, and he really wants to celebrate her life and his relationship with her in that book.
“I think as much as the press want this to be a burn book and an attack on the institution, this is more just about his story, and of course, his story is so much more than just the few years of his life as the Duke of Sussex.
“I think for people expecting that warts and all moment, it’s not going to happen. That said, it’s still going to be fascinating.”
Last month, The Daily Mirror reported that the book will make Harry’s views about his stepmother Camilla known.
A friend of the Prince told The Mirror that the memoir could “shake the monarchy to the core”.
Prince Harry has yet to say anything about the news that Camilla will in effect be the next Queen when his father ascends to the throne.
According to The Daily Mirror, this “speaks volumes” of what he might include in the memoir, insisting that Harry isn’t close to Camilla.
However, royal author Andrew Morton, who wrote a biography of Princess Diana, told the Royally Us podcast that Prince Charles could be in “the firing line” when the book is published.
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There has also been concern raised among royal experts that Harry’s book will overshadow the Queen’s Platinum Jubilee.
Grant Harrold, a former royal butler, told the Express.co.uk last year: “It’ll be covered in the press, bits pulled out of course that are the strongest parts of it, it’ll be discussed and it could potentially be all about the same time.
“So I think the thing is, it could overshadow it and only time will tell.”