UK's Prince Charles, the eldest son and heir to Queen Elizabeth II, has tested positive for coronavirus.

The 71-year-old is displaying mild symptoms of COVID-19 "but otherwise remains in good health," Clarence House said in a statement.

He is now self-isolating and has been working from his home on the Balmoral Estate in Scotland, his office said, adding that it was not possible to ascertain from whom the Prince caught the virus.

Duchess of Cornwall has also been tested but did not have the virus.

A royal source said the Prince of Wales was tested on Monday and got the results on Tuesday. Charles has spoken to both Queen Elizabeth and his children.

"Her Majesty The Queen remains in good health," Buckingham Palace said.

"The Queen last saw The Prince of Wales briefly after the investiture on the morning of 12th March and is following all the appropriate advice with regard to her welfare."