Her Majesty was due to attend a military celebration in Wales during the country's St David's Day celebrations, but was forced to cancel her planned engagements.
Buckingham Palace declined to comment on her condition, but a spokeswoman earlier confirmed the Queen would spend the weekend at Windsor.
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A woman was stabbed to death by a man to stop her accusing another man of indecent assault, a court has heard.
Tuesday afternoon's forecast for the east of the region
Tuesday afternoon's forecast for the west of the region