King Charles was once smitten with a Hollywood actress — "Funny Girl" star Barbra Streisand.

The claim was made by royal author Christopher Andersen in his upcoming book out Nov. 8, "The King: The Life of Charles III." In it, he claims Queen Elizabeth II’s eldest son had a crush on the Hollywood star and long kept a photo of her in his room at Buckingham Palace.

"Barbra Streisand is my only pinup!" Charles once said, according to Andersen.

Andersen claimed Charles first became fascinated with the singer and actress while studying at Cambridge University in the late ‘60s. While his peers listened to the Rolling Stones and Led Zeppelin, Charles played Streisand’s albums "constantly."

KING CHARLES HAD VALETS SQUEEZE OUT HIS OWN TOOTHPASTE, HAND-WASH UNDERPANTS, ROYAL AUTHOR CLAIMS

American singer and actress Barbra Streisand at a reception

American singer and actress Barbra Streisand is seen here visiting London for the royal premiere of the film "Funny Girl," circa 1969. (Central Press/Hulton Archive/Getty Images)

"A personal favorite: the soundtrack from the 1968 film for which she won an Academy Award, ‘Funny Girl,’" Andersen wrote, as quoted by Page Six Thursday. "He saw it three times. A framed photograph of Streisand hung in his rooms at Cambridge and went up on the wall of his bedroom at Buckingham Palace after graduation."

Andersen claimed Charles requested to meet Streisand on the Columbia Pictures set of the "Funny Girl" sequel, 1975’s "Funny Lady." The prince and his "pinup" met and spoke for 15 minutes. According to Andersen, Charles later wrote in his journal that he "really wanted to get to stay and know her," but she insisted on getting back to work. Charles reportedly wrote, "I still contend she has great sex appeal after meeting her."

Barbra Streisand, King Charles and Joan Collins

Barbra Streisand, King Charles and Joan Collins (Getty Images)

It wouldn’t be the last time the pair saw each other. In 1994, Streisand serenaded Charles with "Someday My Prince Will Come" at a gala concert at Wembley Arena in London. And then, six months later, the pair met up for what a palace spokesman said was "a private tea" during the royal’s visit to Los Angeles.

In 2021, Streisand confirmed to U.K. presenter Ross King that Charles requested to meet her while she was recording in San Diego in 1974. At the time, the royal was 26 years old and serving in the Royal Navy.

CLICK HERE TO SIGN UP FOR THE ENTERTAINMENT NEWSLETTER

U.S. actress and singer Barbara Streisand offers a cup of coffee to Prince Charles

Barbra Streisand said she became friends with fan King Charles. (AP Photo/DFS)

"We became friends, and I loved spending some time at Highgrove for a weekend fundraiser and going through his gardens," said the 80-year-old.

Streisand also recalled how, sometime later, she was staying at a hotel in London when she spotted freshly cut flowers on the table.

"I said, ‘Who sent me that?’" Streisand recalled. "[My assistant] said, ‘A fan called Charles.’ And I said, ‘Really? Let me see this note.’ And there was his seal. And they weren’t like from a florist because they were from his gardens, and it’s a different look."

Streisand noted that her closeness with Charles, now 73, "was before he met [Princess] Diana."

Prince Charles smiling at Barbra Streisand

Prince Charles smiles as he meets Marvin Hamlisch, fourth from right, Martin Erlichman, second from right, and Barbra Streisand backstage during a champagne reception ahead of a gala performance in aid of The Prince's Trust at Wembley Arena April 25, 1994, in London. (Anwar Hussein/Getty Images)

"I had a very funny line on stage when he came to see [my show]," she said. "I said, ‘You know, if I played my cards right, I could have wound up being the first Jewish princess!"

Charles previously told the Times of London he’s "always been a great admirer of the incredibly versatile American actress and singer Barbra Streisand." At the time, he was discussing his selection of some of his favorite tracks for a Hospital Broadcasting Association program.

Prince Charles meets Joan Collins on the red carpet

Britain's Prince Charles, meets Joan Collins, Sir Ben Kingsley, Pixie Lott and Luke Evans during the Prince's Trust and Samsung Celebrate Success Awards at Odeon Leicester Square in Central London March 12, 2014. (David M. Benett/AFP via Getty Images)

KING CHARLES TRAVELS WITH HIS TEDDY BEAR, CUSTOM-MADE TOILET SEAT, AUTHOR CLAIMS: 'HE WANTS WHAT HE WANTS'

Andersen claimed Streisand wasn’t the only actress Charles swooned over. The king was reportedly smitten with "Dynasty" star Joan Collins after they danced during a royal tour of the U.S. in 1985.

According to the book, Charles wrote in a letter that Collins, now 89, "was very amusing and with an unbelievable cleavage! All raised up and presented as if on a tray!"

A Buckingham Palace spokesperson previously told Fox News Digital, "We don't comment on such books."