Queen Elizabeth, 95, has tested positive for COVID and is experiencing mild symptoms, Buckingham Palace said on Sunday.
"The queen has today tested positive for COVID," the Palace said. "Her Majesty is experiencing mild cold like symptoms but expects to continue light duties at Windsor over the coming week.
"She will continue to receive medical attention and will follow all appropriate guidelines."
Charles, 73, the heir to the throne, earlier this month pulled out of an event after contracting coronavirus for a second time. A palace source said he had met the queen just days before.
The health of the queen, the world's oldest and longest-reigning monarch, has been in the spotlight since she spent a night in hospital last October for an unspecified ailment and then was advised by her doctors to rest.
Elizabeth on Wednesday quipped to members of the royal household that she could not move much as she carried out her first in-person engagement since Charles tested positive.
India capped airfares on Saturday as hundreds of passengers gathered outside Bengaluru and Mumbai airports after IndiGo cancelled 385 flights on the fifth day of a crisis at the country's biggest airline that has crippled air travel.
Pakistan and Afghanistan exchanged heavy fire along their border late on Friday, officials from both countries said, killing at least five people amid heightened tensions following failed peace talks last weekend.
Negotiations on consolidating the US-backed truce in the war in Gaza are at a "critical" moment, Qatar's Prime Minister Sheikh Mohammed bin Abdulrahman al-Thani said on Saturday.
Residents in the Indonesian region of Aceh Tamiang climbed over slippery logs and walked for about an hour on Saturday to get aid, as the death toll from floods and landslides that hit Sumatra island this month rose to more than 900 people.
A railway hub near Kyiv was attacked during a large-scale Russian drone and missile attack that damaged the depot and railway carriages, Ukrainian state railway company Ukrzaliznytsia said on Saturday.