"It really just says get over yourself, you're not a victim and you were part of a noble cause as the torch bearer of the Invictus and what you're doing now and what you're doing to your family is, I think, inappropriate," Harry's pal penned in a note under the pseudonym Edward Charles Featherstone.
The Duke of Sussex and his wife, Meghan Markle, painted the Windsors as bigoted and unaccepting of the Suits star due to her ethnicity and nationality. However, the royals addressed the accusations, saying "recollections may vary'' in their official statement.
"I've written a letter to him which at some stage I will publish," the insider continued.
The source later revealed he hasn't decided which platform he wants to share his message on.
"Whether I do it lowkey on the H2Z website or the Rude Chronicles website, or whether I do it slightly more upbeat and take a page in the LA Times remains to be seen. But at some point, I will probably publish that letter," he explained.
"It was with great sadness for both of us that my wife and I felt forced to step back from this role and leave the country in 2020. The U.K. is my home," Harry said in his 2023 court witness statement.
"That cannot happen if it’s not possible to keep them safe when they are on U.K. soil. I cannot put my wife in danger like that and, given my experiences in life, I am reluctant to unnecessarily put myself in harm’s way too," he added.
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"And we said, specifically, ‘We’re stepping back from senior roles to be just like several . . .’ I mean, I can think of so many right now who are all . . . they’re royal highnesses, prince or princess, duke or duchess . . . who earn a living, live on palace grounds, can support the Queen if and when called upon. So we weren’t reinventing the wheel here," she confessed.
Featherstone spoke to the The Mirror.