Queen Elizabeth II and heir to the throne Prince Charles both postponed upcoming engagements in Britain and abroad on Friday because of the coronavirus outbreak, the royal household said.
The 93-year-old monarch had been due to visit Cheshire in northwest England, and Camden, in north London, from next week, while her son, 71, was set to tour Bosnia, Cyprus and Jordan.
Buckingham Palace said the queen's diary commitments had been changed "as a sensible precaution and for practical reasons in the current circumstances".
"In consultation with the Medical Household and Government, Her Majesty's forthcoming visits to Cheshire and Camden will be rescheduled," it said in a statement.
"Audiences will continue as usual. Other events will be reviewed on an ongoing basis in line with the appropriate advice."
The queen — Britain's longest-serving monarch — turns 94 on April 21. She also has a second birthday party in June, which is marked with a public parade.
The announcement came as the English Premier League suspended all fixtures until April 4 in a wave of postponements and cancellations of public events in Britain and around the world.
The British government said Thursday it would not ban mass gatherings as scientific advice indicated there was less risk of transmitting the virus than in smaller venues.
But as the number of confirmed cases in the country jumped to 798, with 10 deaths, a string of events were cancelled, from rugby matches to London's annual St Patrick's Day celebrations.
Thousands of people typically turn out to greet the queen on royal visits.
Earlier, Prince Charles' office at Clarence House said it had postponed his planned eight-day trip to Bosnia, Cyprus and Jordan.
He had been due to begin the tour on Wednesday, with his wife, Camilla, Duchess of Cornwall, 72, joining him on the last two legs.
Clarence House said the decision was taken "owing to the unfolding situation with the coronavirus pandemic".
British media said there was no concern for Charles and Camilla's health, and the tour may be replaced with domestic engagements, although not ones involving large crowds.
The queen no longer undertakes overseas visits but has carried out engagements in Britain since the start of the outbreak, including investiture ceremonies at Buckingham Palace.
Her most recent made headlines because she wore gloves but there was no official reason for her wearing them, and she has previously been pictured in them.
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