The King will participate in this year's birthday parade – known as Trooping the Colour - but will travel via carriage instead of horseback, it has been confirmed by Buckingham Palace.
Charles, 75, who has been undergoing treatment for an undiagnosed form of cancer since February, will inspect the soldiers from an Ascot landau carriage with Queen Camilla by his side.
Last year, Charles was the first monarch to ride horseback at the event since Queen Elizabeth II in 1986.
Meanwhile, Lieutenant General James Bucknall, KCB, CBE, will carry out the role of Inspecting Officer on behalf of the Princess of Wales at the Colonel's Review on 8 June as Kate continues her recovery from having preventative chemotherapy for her own cancer diagnosis.
The former Commander of the Allied Rapid Reaction Corps has attended every King's Birthday Parade since 2009 when he was appointed Colonel of the Coldstream Guards, having served as a Coldstream Guards Officer for more than 45 years.
Trooping the Colour, which traditionally involves the royal family gathering on the balcony of Buckingham Palace after a display of pomp and military pageantry, is set to take place on Saturday 15 June.
It comes after the royal family has postponed engagements "which may appear to divert attention or distract from the election campaign" after Prime Minister Rishi Sunak last week called a surprise summer General Election for 4 July, but have continued with garden parties at Buckingham Palace and the King and Queen’s D-Day 80th anniversary appearances in Portsmouth and Normandy in June are expected to go ahead as scheduled.
Which royals will go?
While it has been confirmed that the King and Queen will be in attendance, it has not been confirmed whether the Prince and Princess of Wales and their three children, Prince George, ten, Princess Charlotte, nine, and six-year-old Prince Louis will take part in the parade.
In recent years, Kate has travelled in a carriage with her children to watch the ceremony at Horse Guards Parade.
Last year, Prince William, the Princess Royal and the Duke of Edinburgh all joined the King on horseback for his first Trooping as monarch.
Only senior working royals gathered on the Buckingham Palace balcony to watch the flypast after the review.
During the late Queen Elizabeth II's reign, she invited extended members of the royal family to watch the military spectacle.