Meghan Markle once complained about "not getting paid" for going on a walkabout while on tour with Prince Harry, a royal book has claimed.

King Charles and Queen Camilla are heading Down Under this week for their first royal tour in the country since 2018.

And it was in the same year that the Duke and Duchess of Sussex embarked on their own royal tour in Australia following their wedding a few months earlier.

It was their first joint tour as a married couple and they spent 16 days visiting Australia, Fiji, Tonga and New Zealand.

But according to the book Courtiers: The Hidden Power Behind the Crown, while Meghan "enjoyed the attention" she received, she did not fully comprehend the point of royal walkabouts.

Author Valentine Low wrote: "On the South Pacific tour, Harry and Meghan were going down a storm.

"Massive crowds were turning out to see them, and Meghan’s refreshingly informal approach to royal visits was proving a hit with the Australian public."

He added: "Behind the scenes, however, it was a different story. Although she enjoyed the attention, Meghan failed to understand the point of all those walkabouts, shaking hands with countless strangers.

"According to several members of staff, she was heard to say on at least one occasion: 'I can't believe I’m not getting paid for this'."

A "walkabout" is when royals meet and greet members of the public during their appearances.

It has been reported that Queen Elizabeth first introduced it in 1970 during a royal tour of Australia and New Zealand when she left her car and went on to greet the public.

Elsewhere in the book, an insider claimed that after seeing royal fans gathering outside the Sydney Opera House, Meghan said to the team: "What are they all doing here? It’s silly."