King Charles was joined by King Abdullah II of Jordan and Grand Duke Henri of Luxembourg as the monarch inspected the 200th Royal Military Academy Sandhurst's Sovereign's Parade.
King Abdullah was accompanied by his son and heir, Crown Prince Al Hussein, for the ceremony, and it comes just weeks after the Jordan royal family celebrated Princess Iman's wedding. Take a look back at that special day...
The Jordanian king, 61, graduated from Sandhurst in 1981, while Crown Prince Al Hussein followed in his father's footsteps in 2017.
During the ceremony, King Abdullah presented the Royal Military Academy Sandhurst’s Al Hussein Medal to Bahraini Officer Cadet Sheikh Al Waleed Khalid Ahmed Al Khalifa, which is awarded to non-British cadets who showed the most significant improvement in performance during training.
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Meanwhile, Grand Duke Henri, 68, completed his training at the military academy in 1975.
The visiting royals were pictured with King Charles in an image shared by The Royal Hashemite Court.
Several foreign royals have confirmed their attendance this week for the King's coronation in London on 6 May, including the Swedish, Danish and Spanish households.
Grand Duke Henri's visit to London comes just weeks after he and his wife, Grand Duchess Maria Teresa welcomed the arrival of their sixth grandchild.
Hereditary Grand Duke Guillaume and Hereditary Grand Duchess Stephanie have become parents for the second time with the birth of Prince François on 27 March.
The couple shared the first adorable photos of their second son, who is third in line to the throne after his big brother, Prince Charles, who turns three next month.
The Luxembourg royals are set for more celebrations this month as Grand Duke Henri's only daughter, Princess Alexandra, will wed Nicolas Bagory in a civil ceremony on 22 April, followed by a religious ceremony on 29 April.
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