A statement released by the Danish royal courts said: "Due to stricter entry requirements at the Olympic Games, this means that the crown prince does not have the opportunity to travel to Japan."
WATCH: Princess Anne wishes Team GB good luck ahead of Tokyo Olympics
It added that Crown Prince Frederik, who has been vaccinated, is now self-isolating at home in line with Denmark's guidelines. His wife, Crown Princess Mary, and their four children, Prince Christian, 15, Princess Isabella, 14, and ten-year-old twins, Prince Vincent and Princess Josephine have not come into close contact with the positive case and will not be required to quarantine.
Crown Prince Frederik had been due to fly to Japan on 19 July in order to participate in the 138th International Olympic Committee (IOC) General Assembly between 20 and 21 July, before attending the opening ceremony on Friday. He will attend the General Assembly virtually instead.
Crown Prince Frederik carried the Olympic torch at the London 2012 Games
The Tokyo Olympics had been due to take place in summer 2020 but was postponed by a year due to the pandemic.
The Princess Royal wished Team GB good luck ahead of the Games in a heartfelt video message, telling athletes: "This is your Olympics. It will be different, but not in its importance to you. Savour it, and above all, enjoy it.
"Good luck, and I look forward to celebrating your achievements with you in the autumn."
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