In a tweet, Prince William and Kate wrote: "Wishing all the athletes and staff @TeamGB the best of luck this #Tokyo2020 #Olympics. Although it won't be like previous Games, enjoy it and we know you'll do the nation proud."
WATCH: Prince William surprises Team GB's Lauren Price with birthday cake
The Cambridges joined the Queen, whose royal family Twitter account reshared a moving video from Team GB's official page, adding: "Wishing #TeamGB every success at the #Tokyo2020 #Olympics. 'I and the whole nation will be cheering you on and proudly supporting you from home' – The Princess Royal, President @TeamGB."
The Tokyo Olympics had to be postponed last year due to the pandemic.
The monarch famously participated in the opening ceremony of the London 2012 Olympics, appearing in a James Bond sketch with Daniel Craig.
The Queen at the London 2012 Olympics opening ceremony
The Duke and Duchess of Cambridge also showed their support throughout the Games, attending various events, including cheering on William's cousin, Zara Tindall, in Team Eventing.
Zara won a silver medal, which was proudly presented to her by her mother, Princess Anne.
The Princess Royal became the first member of the royal family to compete in the Olympic Games when she rode the Queen's horse, Goodwill, in the equestrian three-day event at the 1976 Montreal Olympic Games.
William and Kate showed their support at the London 2012 Olympics
Earlier this week, William also sat down with Team GB boxer Lauren Price for a special interview at Kensington Palace.
The Duke presented the Olympic medal hopeful with a personalised birthday cake.
It's been a special week for the Cambridges, who celebrated Prince George's eighth birthday on Thursday.
The family-of-five are thought to be enjoying the school holidays.
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