Meghan Markle was moved to tears following Prince William's defiant statement, as recounted by her husband, Prince Harry, in their Netflix show.
Harry discussed William's response to rumours suggesting he had pressured Harry and Meghan to leave the royal family.
Speaking in the fifth episode of the series, Harry said: "I mean, the saddest part of it was this wedge created between me and my brother so that he's now on the institution's side.
"And I get, part of that I get. I understand, right? That's his inheritance, so to some extent it's already ingrained in him that part of his responsibility is the survivability and the continuation of this institution.
"That day, a story came out that part of the reason why Meghan and I were leaving was because William had bullied us out."
Harry continued: "And once I got in the car after the meeting, I was told about a joint statement that had been put out in my name and my brother's name squashing the story about him bullying us out of the family.
"I couldn't believe it. No one had asked me permission to put my name to a statement like that. And I rang [Meghan] and I told her and she burst into floods of tears because within four hours they were happy to lie to protect my brother and yet for three years, they were never willing to tell the truth to protect us."
The statement in question read: "Despite clear denials, a false story ran in a UK newspaper today speculating about the relationship between the Duke of Sussex and the Duke of Cambridge.
"For brothers who care so deeply about the issues surrounding mental health, the use of inflammatory language in this way is offensive and potentially harmful."
Harry and Meghan spoke about a range of topics in their Netflix show, including their difficult relationship with the tabloid press, and the Royal Family's response to racist news articles written about Meghan.
"The direction from the Palace was don't say anything," said Harry. "But what people need to understand is, as far as a lot of the family were concerned, everything that she was being put through, they had been put through as well.
"So it was almost like a rite of passage, and some of the members of the family were like 'my wife had to go through that, so why should your girlfriend be treated any differently? Why should you get special treatment? Why should she be protected?' "I said, 'the difference here is the race element'."
He further said that there is a "huge level of unconscious bias" in the Royal Family, adding: "It is actually no one's fault. But once it has been pointed out, or identified within yourself you then need to make it right."
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