Both Charles and his daughter-in-law, Princess Kate, are undergoing cancer treatment.

Ms Harris continued: “During the reigns of Queen Elizabeth II and King Charles III, Scotland week has taken place in July, a time when the monarch hosts garden parties and investitures and undertakes public engagements in Scotland.”

In Scotland, it is referred to as Royal Week or Holyrood Week, when the monarch comes to visit and travels to different regions.

Also in July, Charles will be busy with the State Opening of Parliament following the United Kingdom general election, says Ms Harris.

She added: “The time to rest and regroup will be later in the summer, after the State Opening of Parliament.”

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We asked Ms Harris if there is anything particular she’s looking forward to, and there is: the opening of the East Wing of Buckingham Palace and guided tours of Balmoral Castle.

“King Charles III is making royal residences more accessible to the public this summer," she explained.

But while Queen Elizabeth II spent much of her summer holiday at Balmoral, Charles prefers nearby Birkhall, she said.

The Buckingham Palace and Balmoral Castle tours have already sold out with Ms Harris saying access to historical royal residences will most likely increase in future years.