The 94-year-old Queen and 99-year-old Prince Philip have been at the castle since March because of the threat of coronavirus infection, which is far deadlier for elderly people.
Buckingham Palace will be closed for the summer and events including Trooping the Colour and Her Majesty’s garden parties cancelled.
The isolation marks what is believed to be Queen Elizabeth’s longest absence from official duties in her 68 year reign. While there is no time frame for resumption of duties, the fall has been targeted as the earliest possible date.
While isolated, the Queen and Prince Philip are being served by a small household staff. She still has a weekly audience with the Prime Minister by phone and receives daily boxes of government papers.
The Queen and the Duke of Edinburgh usually return from Windsor in May before an annual break at Balmoral in July.
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