HRH The Duke of Edinburgh, Prince Philip.
Prince Philip, the Duke of Edinbugh, has died aged 99.
In a statement the Royal Family 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 Royal Family join with people around the world in mourning his loss. Further announcements will be made in due course.”
The Duke, who was Queen Elizabeth II's husband of 73 years, was the longest-serving royal consort in British history.
The couple had four children, eight grandchildren and 10 great-grandchildren.
On behalf of the Northern Ireland Executive, First Minister Arlene Foster and deputy First Minister Michelle O’Neill have expressed their sympathies following the death of the Duke of Edinburgh.
First Minister Arlene Foster said: “I am deeply saddened by the news of the death of His Royal Highness the Duke of Edinburgh. It is a sadness that I know will shared by countless others in Northern Ireland and right across the world.
“Prince Philip was widely respected for his active and dedicated service to the country and for his steadfast support to Her Majesty the Queen throughout her reign.
“He had a strong interest in Northern Ireland and I had the privilege of meeting him on a number of his many visits here.
“He had a profound and positive impact on thousands of our young people who found their purpose, passion and place in the world through participation in the Duke of Edinburgh Awards.
“This inspirational programme is just one example of the many charities and voluntary organisations in which he was involved in right up to his retirement from public service at the age of 96.
“I offer my deepest sympathies and condolences to Her Majesty the Queen and to the other members of the Royal family at this sad time.”
Deputy First Minister, Michelle O’Neill said: “I wish to extend my sincere condolences to Queen Elizabeth and her family on the death of her husband Prince Philip.
“Over the past two decades there have been significant interventions by the British Royal family to assist in the building of relationships between Britain and Ireland
“It is appropriate that this contribution to the advancement of peace and reconciliation is rightly recognised.
“To all those of a unionist tradition and of British identity - those who value and cherish the Royal family - I wish to acknowledge the sense of loss felt.”