Prince Charles, the eldest son and heir to Queen Elizabeth II, is isolating after testing positive for coronavirus for the second time, his office said on Thursday.
"The Prince of Wales has tested positive for Covid-19 and is now self-isolating," said a message on the prince's official Twitter page.
"HRH (His Royal Highness) is deeply disappointed not to be able to attend today's events in Winchester and will look to reschedule his visit as soon as possible," it added.
He was due to unveil a statue in the southern city later Thursday.
The 73-year-old heir-to-the-throne also tested positive in March 2020 and spent around a week isolating at the Queen's Balmoral estate in Scotland.
His office did not say when he was last in contact with his 95-year-old mother, who herself has had recent health problems that forced her to take a step back from official duties.
However, she is once again filling up her diary as a year of celebrations began this week to mark her 70 years on the throne.
On Wednesday, he attended a reception at the British Museum for the British Asian Trust where pictures showed him chatting to other guests, including British finance minister Rishi Sunak. Health minister Sajid Javid and interior minister Priti Patel were also among those who were due to attend.
There was no immediate comment on his condition.
The prince, who said in December both he and his wife Camilla had received their Covid vaccine booster shots, previously tested positive in March last year when he said he had been "lucky" to have suffered only mild symptoms.
He spent seven days in self-isolation at his Birkhall home in Scotland before resuming his duties.
His son Prince William also contracted Covid shortly after his father in 2020, with media reports saying he had been hit badly by the virus.
