Princess Diana’s hairdresser has weighed in on the controversy surrounding Prince Harry and her riding instructor James Hewitt.

After years of rumours and speculations that Princess Diana’s riding instructor James Hewitt, and not King Charles, is the biological father of Prince Harry, a new memoir has shed some light on the nature of their relationship. For years, a few similarities between Hewitt and Harry — ginger hair and freckles — led to such rumours.

Richard Dalton, Diana’s hairdresser, has now weighed in on the controversy and even detailed his friendship with the late Princess in a new memoir, “It’s All About the Hair”.

“It’s not possible,” Dalton told Fox News Digital.

“It was tough… Harry was already born a while before her relationship with Hewitt. And I don’t think it’s possible.” To support his statement, Dalton claimed even Princess Diana’s brother and sister had “bright red hair”.

“Harry and the Spencer family have red hair. Charles, Diana’s brother, had bright red hair when he was (in) college,” he said, adding he used to cut his hair back then.

He added that Sarah, Diana’s sister, also has bright red hair, while her other sister Jane was “more or less the same colouring as Diana.”

In his book, Dalton said that Diana “used to get very upset” over the reports of Hewitt being called Harry’s father, adding that the “red hair was a trait from the Spencer family”.

Diana and Hewitt met each other for the first time in 1986, two years after Harry’s birth in 1984, according to reports.

Harry was born “long before Diana even met James Hewitt,” Dalton wrote in his book, adding the two had a “love affair,” which lasted three years between 1989 and 1991. Both Harry and Hewitt have addressed the rumour in the past.

Last year, Harry sued an outlet for apparently using unlawful techniques “on an industrial scale” to score on his life.

“Numerous newspapers had reported a rumour that my biological father was James Hewitt, a man my mother had a relationship with after I was born,” Harry said in a written statement.

“At the time of this article and others similar to it, I wasn’t actually aware that my mother hadn’t met Major Hewitt until after I was born,” he added.

In 2002, Hewitt himself addressed the gossip and said, “There really is no possibility whatsoever that I am Harry’s father. I can understand the interest, but Harry was already walking by the time my relationship with Diana began.”