The Prince of Wales, 71, is displaying mild symptoms “but otherwise remains in good health”, a spokesman said, adding that his wife Camilla, the Duchess of Cornwall, 72, has been tested but does not have the virus.
“It is not possible to ascertain from whom the Prince caught the virus owing to the high number of engagements he carried out in his public role during recent weeks,” he added.
Both Prince Charles and Camilla are now self-isolating at Balmoral in Scotland.
Buckingham Palace said Queen Elizabeth last saw her son on March 12, but she “remains in good health.”
The Queen, the Palace added, “is following all the appropriate advice with regard to her welfare.”
On Wednesday the number of coronavirus cases in the UK jumped by 1,427 to 8,077. There have been 422 deaths there due to the virus so far.