King Charles disregarded Princess Anne's warning regarding a slimmed-down monarchy, a royal historian told GB News.
Ahead of the Coronation, the Princess Royal offered an interview in which she opposed the idea of reducing the number of active members within the Royal Family.
She said: "Well, I think the 'slimmed-down' [monarchy] was said in a day when there were a few more people around to make that seem like a justifiable comment."
Two royals that are frequently named as possibilities for working royals are Princess Beatrice and Princess Eugenie, the Duke of York's daughters.
The demand for more working royals has increased ever since King Charles and Princess Kate stepped back from royal duties due to their various health concerns.
Marlene Koenig, a royal historian, spoke exclusively to GB News where she explained that the York Princesses would not be available to stand in for the Princess of Wales.
She said: "Each royal has their own engagements, their own charities, foundations, patronages, and interests.
"Beatrice and Eugenie cannot step in for Catherine with her engagements for this reason."
According to Koenig, King Charles has no plans to listen to Princess Anne's "warnings" about a smaller Royal Family.
She explained: "The Princess Royal has alluded to problems with a smaller Royal Family, but the King has not heeded her warnings.
"Beatrice and Eugenie are Prince Andrew’s daughters, which, of course, would cause criticism from some quarters."
Read More: Princess Anne stirred up conflict between King Charles and Prince Harry
The Duke of York stepped down from royal duties in 2019 after his infamous Newsnight interview with Emily Maitlis, where he discussed his friendship with the late convicted sex offender, Jeffrey Epstein.
Sarah Ferguson's daughters are both married and have children of their own.
In addition, Beatrice, 35, and Eugenie, 33, are patrons of various charities and hold their own jobs.
Read More: Princess Anne treats King Charles as child to make him happy
Princess Beatrice, who is married to Edoardo Mapelli Mozzi, lives in an apartment in St James's Palace in London.
Meanwhile, Princess Eugenie and her husband Jack Brooksbank live abroad in Portugal with their sons, August, three, and eight-month-old Ernest.
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