Prince Williamis leading the rehearsals for his fatherKing Charles' big birthday parade.

The Prince of Wales, 40, cast his eye over the last big practice beforeTrooping the Colour, the annual public celebration of the British monarch’s birthday, which will take place at Horse Guards Parade on June 17 this year. The festivities will mark thefirst birthday parade of King Charles' reign, although Queen Elizabeth held the annual event around the same time of year.

On Saturday morning, Prince William proudly ensured the Welsh Guards regiment — of which he’shonorary Colonel— and the others from the household division were well-prepared for next Saturday’s parade. The Welsh Guards have the honor of Trooping the Colour at the parade this year – their flag will be presented in front of the King.

“The purpose of the Colonel’s review is to decide that they are ready for the monarch,” an army source told PEOPLE.

Prince William, Prince of Wales.Stuart C. Wilson/Getty

Prince William, Prince of Wales Carries Out The Colonel’s Review at Horse Guards Parade on June 10, 2023 in London, England.

Stuart C. Wilson/Getty

The Prince of Wales led the parade down the Mall in London on horseback. He wore the Guard of Honour Order, complete with a bearskin cap, tunic, garter sash and sword.

Prince William, Prince of Wales.ADRIAN DENNIS/AFP via Getty

Britain’s Prince William, Prince of Wales, carries out the Colonel’s Review at Horse Guards Parade in London on June 10, 2023 ahead of The King’s Birthday Parade.

ADRIAN DENNIS/AFP via Getty

The parade will be a year of firsts — the initial one for the King and the first one for William as Prince of Wales. It was also the first time Prince William has taken on the rehearsal role since he was made ceremonial Colonel of the Welsh Guards shortly after the death ofQueen Elizabethin September. Hedid undertake the Colonel’s reviewwhen he was Colonel of the Irish Guards last year — a role thatnow belongs to his wife, Princess Kate.

Prince William, Prince of Wales Carries Out The Colonel’s Review at Horse Guards Parade on June 10, 2023 in London, England.

As the practice review took place on Saturday morning, Prince William’s office released some details of some of the duties the Welsh Guards have undertaken in the past year. They were part of the multinational force that designed and implemented the U.K. training package for Ukrainian soldiers “to gain the infantry skills they need to defend their homeland,” Kensington Palace said. “Alongside this, they have carried out jungle training exercises in Belize and Jamaica, as well as taking part in ceremonial duties for the Coronation of Their Majesties The King and Queen.”

Prince William, Prince of Wales Carries Out The Colonel’s Review at Horse Guards Parade on June 10, 2023 in London, England. The Prince of Wales carried out the review of the Welsh Guards for the first time as Colonel of the Regiment.

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source: people.com