Prince Harry and Meghan Markle have an "us against the world" attitude and are "addicted to drama", a royal expert has said.
According to author and ex-Vanity Fair editor Tina Brown, Harry believes he can "save Meghan" in a way he couldn't save his mother.
And Ms Brown, who releases her new book The Palace Papers next month, notes that the dynamic of their marriage is different to that of Harry's brother and sister-in-law the Duke and Duchess of Cambridge.
In an interview with The Telegraph, she said: "William and Kate calm each other down a lot; their marriage works very well in that way.
"In the Sussex marriage, they wind each other up and it’s Us Against the World, and that’s a disaster."
Ms Brown also went on to say that if Harry and Meghan had remained as working royals, they would have been great assets to the Commonwealth.
But she added that they gave up on royal life too soon and explained: "They didn't understand that the Queen was giving them this platform for soft power which could have been tremendous if they had done it in a patient and strategic way."
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Ms Brown's new book, The Palace Papers is set to be released later this month.
The publisher claims it will tell the "real story" of the royals since Princess Diana's death in 1997 - and is "full of nuanced details and searing insight".
It also adds that the author developed the book from her "years of research" and "intimate access" to the royals and will chart the Queen's "loosening grip" on the Firm.
Meanwhile, last night it was confirmed that Meghan will embark on her first trip outside of the US since she quit the royal family by travelling with Harry to the Invictus Games in Holland this week.
The Mirror revealed on Saturday that Harry and Meghan will be followed by a Netflix documentary crew throughout the Games, which start on Saturday.
The couple’s decision to attend the event in The Hague has been blasted by palace insiders after Harry claimed it was “too dangerous” to travel to the UK.
He is locked in a legal battle with the UK government over a decision to downgrade his security and did not show up at a memorial service for his grandfather, Prince Philip, last month.
