Beatrice and Eugenie are not working royals, meaning they have their own jobs outside the Firm and are not funded by the UK taxpayer.

However they are still invited to appear at occasional royal events to support the family, as they both attended a garden party last month hosted by their cousin Prince William.

There had been rumours that they would be seen on the Buckingham Palace balcony for Trooping the Colour on June 15 to boost royal numbers, with Princess Kate and her children unlikely to attend.

But one royal expert has quashed this, with author Tom Quinn telling The Mirror: ” As his two cousins pivot towards his exiled brother, and with his wife and father incapacitated by illness, William feels increasingly isolated and in the closed hothouse atmosphere of Kensington Palace and Windsor he is bound to feel increasingly paranoid.

“For William it’s a question of loyalty – as Beatrice and Eugenie have got closer to Harry William has decided to keep them very much at arm’s length.

“The two sisters are known to be close to William’s brother, Harry, with the Duke of Sussex thinking his cousins can ‘sympathise’ with him the most.”