The Princess of Wales will make her first public appearance this year at Trooping the Colour.
Kate, who has been receiving treatment for an undisclosed form of cancer since late February, will ride in a carriage alongside her three children, Prince George, Princess Charlotte and Prince Louis.
Later, she is expected to join the King, her husband the Prince of Wales, and other royals on Buckingham Palace’s balcony for the fly-past.
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The princess, 42, said: “I’m looking forward to attending the King’s Birthday Parade this weekend with my family and hope to join a few public engagements over the summer, but equally knowing I am not out of the woods yet.
“I am learning how to be patient, especially with uncertainty.
“Taking each day as it comes, listening to my body, and allowing myself to take this much needed time to heal.”
The Royal Family at last year’s Trooping the Colour. Pic PA
A Buckingham Palace spokesperson said: “His Majesty is delighted that the princess is able to attend tomorrow’s events, and is much looking forward to all elements of the day.”
Rishi Sunak and Sir Keir Starmer welcomed the news on social media, both describing Kate as an “inspiration” to those experiencing similar health issues.
This will be the princess’s first official outing of 2024 after she missed engagements at the start of the year when she was admitted to hospital for abdominal surgery on 16 January.
At the time her condition was thought to be non-cancerous, but tests after the successful operation found the disease, and Kate disclosed the diagnosis in March.
A time frame has not yet been set for Kate’s return to a full schedule of public engagements.
Read more:
Princess of Wales’s statement in full
Princess of Wales, says she’s ‘not out of the woods’
Trooping will be a special event for the princess as Number 9 Company, Irish Guards, a regiment she represents as Colonel, will be Trooping their King’s Colour, but Lieutenant General Sir James Bucknall will take the salute on her behalf.
The King, who is also undergoing cancer treatment, will not ride during the ceremony but will inspect the troops formed up in Horse Guards Parade in Whitehall from a carriage.
Also appearing at the ceremony will be three military horses which bolted across London earlier this year.
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Horses cause ‘mayhem’ in London
Five Household Cavalry Mounted Regiment horses were hurt as they ran through the capital after being spooked by rubble dropped through a plastic tunnel on an exercise in Belgravia on 24 April.
Three steeds, named Tennyson, Trojan and Vanquish, have been confirmed as having roles after recovering in “expert respite care” and the army said the trio showed “aptitude and eagerness”.
Tennyson will be riding in the prestigious Sovereign’s Escort, while Trojan and Vanquish will join the King’s Life Guard at Horse Guards, providing the ceremonial guard for the official entrance to the royal palaces.