Gun salutes to mark the death of the Duke of Edinburgh are due to take place later across the UK, in Gibraltar and from warships at sea.
Prince Philip, Queen Elizabeth II's husband of 73 years, died on Friday.
Aged 99, he was the longest-serving royal consort in British history.
Saluting batteries will fire 41 rounds at one round every minute from 12:00 BST in cities including London, Edinburgh, Cardiff and Belfast, the Ministry of Defence said.
Royal Navy ships at sea, including HMS Diamond and HMS Montrose, will also fire the salute in honour of the duke, who served as a naval officer during World War Two and held the office of Lord High Admiral.
The salutes will be broadcast online and on TV, and the public are encouraged to observe them from home.
Announcing the duke's death on Friday, Buckingham Palace said: "It is with deep sorrow that Her Majesty the Queen announces the death of her beloved husband.
"The Royal Family join with people around the world in mourning his loss."
Reflecting on Prince Philip's life for a BBC programme, the Prince of Wales described his father's life as an "astonishing achievement".
First Sea Lord and Chief of the Naval Staff Admiral Tony Radakin, the most senior officer in the Royal Navy, praised the duke's "empathy, affection and engagement" with the fleet.
"His deep understanding of our values, standards and ethos made him such a close friend to the service for over eight decades," he said.
Admiral Sir Mark Stanhope, who held the position from 2009 to 2013, told BBC Radio 4's Today programme that Philip was an "extremely talented sailor" who was "never shy" when it came to telling first sea lords where he thought they were going wrong.
And Admiral Sir Jonathon Band, Sir Mark's predecessor, told BBC Breakfast that Saturday's military tributes were "a way you say goodbye to great sailors".
The duke was "constantly modernising" and "a great believer that the services have to reflect the society they serve", he added.
General Sir Nick Carter, Chief of the Defence Staff, said the duke had been a "great friend, inspiration and role model" for the armed forces.
"A life well lived, His Royal Highness leaves us with a legacy of indomitable spirit, steadfastness and an unshakeable sense of duty," Sir Nick said.
Similar salutes were fired to mark the death of Queen Victoria in 1901 and Winston Churchill in 1965.
The New Zealand Army will also fire a 41-gun salute in honour of Prince Philip at Point Jerningham in Wellington on Sunday.
Final details of the duke's funeral are also expected to be released this weekend.
The funeral will take place at St George's Chapel, Windsor, but the arrangements have been amended in light of the coronavirus pandemic, the College of Arms said in a statement.
The duke will not have a state funeral and there will be no lying-in-state, in line with his wishes, it added.
Members of the public are "regretfully" requested not to attend due to the pandemic, and it is understood the Queen is considering modified funeral and ceremonial arrangements.
All UK government buildings have been told to fly official flags at half-mast in tribute to the duke until 08:00 on the day after the duke's funeral.
Westminster Abbey tolled its tenor bell once every 60 seconds for 99 times from 18:00 on Friday, to honour each year of the duke's life.
And ahead of the Grand National later, a two-minute silence will be held at Aintree Racecourse in memory of the duke, who was an honorary member of the Jockey Club.
In BBC interviews to mark the Duke of Edinburgh's death aired on Friday night, Philip's children shared their reflections on their father's life - with the Prince of Wales calling his legacy an "astonishing achievement".
Prince Charles said: "His energy was astonishing in supporting my mama [the Queen] - and doing it for such a long time, and, in some extraordinary way, being able to go on doing it for so long.
"What he has done has amounted to an astonishing achievement, I think."
Princess Anne said the duke "treated everyone as an individual, and gave them the respect he felt they were due as individuals".
It is understood that Prince Charles travelled to Windsor Castle to visit his mother on Friday afternoon.
A message on the website of the Duke and Duchess of Sussex's non-profit organisation Archewell paid tribute to the "loving memory" of the Duke of Edinburgh, saying: "Thank you for your service... you will be greatly missed."
Politicians across the UK also paid tribute to the duke, with Prime Minister Boris Johnson saying the duke had "earned the affection of generations" in the UK and around the world.
Political parties suspended their campaigning for elections on 6 May and parliament will honour the duke on Monday, with the House of Commons sitting at 14:30 for tributes.
International leaders also remembered Philip and sent their condolences to the Queen.
US President Joe Biden and First Lady Jill Biden said in a statement the duke "gladly dedicated himself to the people of the UK, the Commonwealth, and to his family".
The announcement also saw members of the public gather outside Buckingham Palace and Windsor Castle to pay their respects.
Prince Philip and the Queen had four children, eight grandchildren and 10 great-grandchildren.
Their first son, the Prince of Wales, Prince Charles, was born in 1948, followed by his sister, the Princess Royal, Princess Anne, in 1950, the Duke of York, Prince Andrew, in 1960 and the Earl of Wessex, Prince Edward, in 1964.
Prince Philip was born on the Greek island of Corfu on 10 June 1921.
His father was Prince Andrew of Greece and Denmark, a younger son of King George I of the Hellenes.
His mother, Princess Alice, was a daughter of Prince Louis of Battenberg and a great-granddaughter of Queen Victoria.
BBC
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