Prince Philip - the Duke of Edinburgh - has died at the age of 99, Buckingham Palace has said.
A statement from the Palace said: "It is with deep sorrow that Her Majesty The Queen has announced the death of her beloved husband, His Royal Highness The Prince Philip, Duke of Edinburgh.
"His Royal Highness passed away peacefully this morning at Windsor Castle."
The duke was married to Queen Elizabeth II for more than 70 years and became the longest-serving consort in British history - he was due to turn 100 in two months' time, on 10 June.
His cause of death has not yet been announced.
Philip had returned to Windsor Castle on 16 March after spending nearly a month in hospital - his longest ever stay.
No official details have been released yet about the Duke's funeral, but it is understood he will be given a royal ceremonial funeral rather than a state funeral, in line with his wishes.
The Queen will sign off the final plans in the coming days.
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