Prince Charles was forced to intervene in a debate about funding for Princesses Beatrice and Eugenie's security causes a row behind palace walls, a royal expert has claimed.
The heir to the throne stepped in after the younger of his nieces racked up huge security costs as she travelled the world on her gap year.
A report published at the time suggested Eugenie, who has recently announced she's pregnant with her first child, spent more than £100,000 of taxpayers' money as she exploded India, America, Thailand and South Africa.
She paid for hotels and travel herself, but the massive security bill, including overtime money, was funded by the taxpayer.
Speaking on Channel 5 documentary Beatrice and Eugenie: Pampered Princesses?, royal expert Richard Kay said: "She was sort of flitting from country to country as most middle-class young people do who take gap years.
"But, of course, she was accompanied by police bodyguards.
"That meant that we the taxpayers were paying for policemen to accompany her to the fleshpots of the world."
Charles reportedly stepped in to control the spending, with author Angela Levin telling the programme he suggested Eugenie and Beatrice didn't need costly security as it's unlikely they will ever become working royals.
The sisters currently sit at ninth and tenth in line to the throne, and will be pushed down even further when Prince George, Charlotte and Louis grow up and have children.
But Charles's suggestion didn't go down well and left Prince Andrew, furious.
Ms Levin added: "Prince Charles decided that as they were not likely to be very senior royals, that this was too much for the public to pay, so he stopped that.
"Prince Andrew was so angry that he wrote a note to the Queen.
"He said he wanted them to be considered as proper royals. He did not want the protection officers to leave them."
Andrew is often described as the Queen's favourite son, and she is extremely fond of him - however she agreed with her first born and refused Andrew's pleas.
