The Queen has tested positive for coronavirus, Buckingham Palace has said.
The monarch, 95, is experiencing mild cold-like symptoms and expects to continue light duties at Windsor this week, the palace said.
She is understood to be triple vaccinated.
Prince Charles tested positive for COVID for the second time this month, with palace sources saying he had seen his mother a few days before then.
The announcement was made just a few weeks after the Queen, Britain’s longest-reigning monarch, reached her historic Platinum Jubilee of 70 years on the throne.
A statement by Buckingham Palace said: “Buckingham Palace confirm that The Queen has today tested positive for Covid.
“Her Majesty is experiencing mild cold-like symptoms but expects to continue light duties at Windsor over the coming week.
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“She will continue to receive medical attention and will follow all the appropriate guidelines.”
The Royal Household has its own royal physicians and the Queen’s doctors will be on hand to take care of and monitor her health.
Professor Sir Huw Thomas, head of the Medical Household and Physician to the Queen, is expected to be in charge.