Prince Harry and his wife Meghan Markle announced that they are suing the 'Mail on Sunday' newspaper after it published one of the Duchess's private letters.
In a statement on the Duke and Duchess of Sussex's official website this evening, Harry said he had been a "silent witness" to Meghan's "private suffering" for too long.
On its part, law firm 'Schillings', representing the duchess, 38, confirmed she had filed a High Court claim. The firm did not explain what letter the court proceedings relate to, but it is understood to be one she sent to her father, Thomas Markle.
Harry, 35, referencing press coverage of his mother Princess Diana, said his "deepest fear is history repeating itself".
"To stand back and do nothing would be contrary to everything we believe in," he wrote.
"The contents of a private letter were published unlawfully in an intentionally destructive manner to manipulate you, the reader, and further the pisive agenda of the media group in question". he added: "Though this action may not be the safe one, it is the right one. Because my deepest fear is history repeating itself."
He wrote: "I’ve seen what happens when someone I love is commoditised to the point that they are no longer treated or seen as a real person.. I lost my mother and now I watch my wife falling victim to the same powerful forces."
[caption id="attachment_82541" align="aligncenter" width="428"] Prince Harry[/caption]
The legal proceedings in the Chancery Division of the High Court are being privately funded by Harry and Meghan.
In return, a Mail on Sunday spokesman said: "The Mail on Sunday stands by the story it published and will be defending this case vigorously. "Specifically, we categorically deny that the duchess's letter was edited in any way that changed its meaning," he added.