Buckingham Palace has announced the death of His Royal Highness, Prince Philip, The Duke of Edinburgh who has died aged 99.
He would have celebrated his 100th birthday in June.
Announcing his passing today, Buckingham Palace said in a statement on Twitter:
"It is with deep sorrow that Her Majesty The Queen has announced the death of her beloved husband, His Royal Highness Prince Philip, The Duke of Edinburgh.
His Royal Highness passed away peacefully this morning at Windsor Castle."
"The Royal Family join with people around the world in mourning his loss."
Prince Philip was hospitalised for a month across February and March at two hospitals where he was treated for an infection and a pre-existing heart condition.
The late Prince Philip and Queen Elizabeth were married in 1947.
They had four children, eight grandchildren and 10 great-grandchildren.
Flags across the nation are being flown at half-mast as a mark of respect.
The Prince was also known throughout the Commonwealth for the Duke of Edinburgh Award Scheme which he established.
Prime Minister Boris Johnson paid tribute in a formal statement on Friday afternoon shortly after the announcement from Buckingham Palace.
"We mourn today with Her Majesty the Queen, we offer our condolences to her and all her family and we give thanks as a nation and a kingdom for the extraordinary work of Prince Philip, the Duke of Edinburgh," the Prime Minister said.
"He helped to steer the Royal Family and the monarchy so that it remains an institution indisputably vital to the balance and happiness of our national life."
Mr Johnson said the Duke of Edinburgh earned the affection of generations in the UK, across the Commonwealth and around the world.
The leader of the opposition Labour Party Sir Keir Starmer said: "The United Kingdom has lost an extraordinary public servant in Prince Philip.”