This happened on Friday morning at King Edward VII hospital to which he was transferred on Tuesday night from Windsor Castle where he had been confined since the start of the pandemic.
Philip of Edinburgh was the father of four children, grandfather of eight grandchildren, and great-grandfather of nine great-grandchildren.
After announcing his official retirement in 2018, Prince Philip made his last public appearance at Windsor Castle in July 2020 when he presented the peerage of Colonel-in-Chief of The Rifles infantry regiment to his daughter-in-law, the Duchess of Cornwall, wife of Prince Charles.
Upon learning of the Prince's death, Labour leader Keir Starmer said the United Kingdom has lost an extraordinary public servant.
Deeply saddened to hear of the passing of Prince Philip, The Duke Of Edinburgh at the age of 99. He fought against the Nazis during the war and was the Husband to the Queen. May he rest in peace ������ pic.twitter.com/ls6fMAJ3Us
"Prince Philip dedicated his life to our country, from a distinguished career in the Royal Navy during the Second World War to decades of service as Duke of Edinburgh," he said.
On Friday morning, the U.K. Prime Minister Boris Johnson recalled the ethical virtues and patriotism of the late member of the British Crown.
"By any measure, Prince Philip lived an extraordinary life - as a naval hero in the Second World War, as the man who inspired countless young people through the Duke of Edinburgh's Award and, above all, as Her Majesty The Queen's Loyal consort," he tweeted.
Scotland's Chief Minister Nicola Sturgeon also expressed her sadness and deep condolences to Queen Elizabeth II and the British royal family.