Charles Spencer fuels rumors Prince Harry is working on a documentary about Princess Diana

Princess Diana’s brother seemingly confirmed in his new book that Prince Harry is working on a documentary about his mother.

In his new bombshell memoir, “Swan Song: Diana, My Sister,” Charles Spencer says he’s chosen now to write his book because of the 30th anniversary of his sister’s death as well as declining “endless” requests to appear in documentaries about her.

“From, to name just a few, a nephew, from Diana’s biographer Andrew Morton, and from Tony Blair’s spin doctor, Alastair Campbell,” he writes, not elaborating on which “nephew” approached him.

“And I thought, You know what? Rather than even contemplate being a talking head in a production that will follow the usual flawed lines, with an agenda set by some TV producer I will never meet, or by a network I will never watch, I am going to tell things how I remember them, lay them down for good, once and for all.”

The news comes as reports Harry is “in talks” to make a documentary, though nothing has been finalized or confirmed yet.

Earlier this month, the Daily Mail reported that “one of the reasons” Harry, 42, returned to the United Kingdom was to “make a television film, his own film, about his mother,” Diana.

The Daily Mail’s Senior Editor-at-Large Richard Kay alleged the “Spare” author “has been reaching out to his friends and others who knew” his mom and “asking them to contribute.”

The royal expert noted that when Harry traveled to the UK back in July, he spent a lot of time with Diana’s family at Althorp.

Kay claimed the alleged project will “occupy a lot of [Harry’s] headspace over the next 12 months” and has caused “intense frustration” for his estranged brother, Prince William.

“She was the mother of two boys,” Kay emphasized. “William is just as much his mother’s son as Harry is, and Harry has tried to claim the Diana legacy for himself.”

“This issue of trying to use Diana, the Spencer brand, the Spencer name, to divide himself away from the House of Windsor, I think is something we’re going to see even more of,” Kay claimed.

Harry and William’s mom, the late Princess of Wales, died in August 1997 at age 36 from severe injuries sustained in a high-speed car crash.

Spencer’s new book, “Swan Song: Diana, My Sister,” which is out now, has several bombshell claims including that Charles sounded like a “lottery winner” when Diana died and that she would be forgotten “soon enough.”

The palace issued a blistering statement about the book, saying that the loss of the Princess of Wales clouded Spencer’s memory.

“His Majesty is mindful that the pain of fraternal grief can cloud reason, affect judgment and color memory in ways others do not recognize, even many years after such a loss,” the rep told Page Six.