US President Joe Biden is among world leaders who have paid tribute to Prince Philip, remembering him for his sense of duty and devotion to the Queen.
The Duke of Edinburgh died on Friday morning at Windsor Castle at the age of 99.
Mr Biden and First Lady Jill sent their “deepest condolences” to the Queen.
The US leader said in a message: “Over the course of his 99-year life, he saw our world change dramatically and repeatedly.
“From his service during World War II, to his 73 years alongside the Queen, and his entire life in the public eye – Prince Philip gladly dedicated himself to the people of the UK, the Commonwealth, and to his family.
“The impact of his decades of devoted public service is eent in the worthy causes he lifted up as patron, in the environmental efforts he championed, in the members of the armed forces that he supported, in the young people he inspired, and so much more.
“His legacy will live on not only through his family, but in all the charitable endeavours he shaped.”
Prince Philip dies – Live reaction from UK and around the world
Mr Biden’s predecessor, Donald Trump, said the Duke “embodied the noble soul and proud spirit of the United Kingdom and the Commonwealth”.
The former US president added: “Prince Philip defined British dignity and grace. He personified the quiet reserve, stern fortitude, and unbending integrity of the United Kingdom.
“He was admired by his fellow citizens, and respected by everyone around the world. His exceptional example of service, constancy, and patriotism will be his greatest legacy.”
Another ex-president, Barack Obama, has recalled when he and his wife Michelle met the Queen and the Duke in the UK during his time as America’s commander-in-chief.
The Queen and Prince Philip with Barack and Michelle Obama at Buckingham Palace in May 2011
Mr Obama said: “The Queen and Prince Philip immediately put us at ease with their grace and generosity, turning a ceremonial occasion into something far more natural, even comfortable.
“Prince Philip in particular was kind and warm, with a sharp wit and unfailing good humour. It was our first introduction to the man behind the title, and in the years since, our admiration for him has only grown. We will miss him dearly.”
He added: “Like the Queen, Prince Philip saw world wars and economic crises come and go. The radio gave way to the television, and the television to the internet. And through it all, he helped proe steady leadership and guiding wisdom.
“At the Queen’s side or trailing the customary two steps behind, Prince Philip showed the world what it meant to be a supportive husband to a powerful woman.
“Yet he also found a way to lead without demanding the spotlight – serving in combat in World War II, commanding a frigate in the Royal Navy, and tirelessly touring the world to champion British industry and excellence.
“Through his extraordinary example, he proved that true partnership has room for both ambition and selflessness – all in service of something greater.”
The royal couple with the Obamas in April 2016
Canada’s Prime Minister Justin Trudeau described Prince Philip as a “man of great purpose and conviction”.
“Prince Philip contributed so much to the social fabric of our country – and the world,” he tweeted.
“He will be remembered as a decorated naval officer, a dedicated philanthropist, and a constant in the life of Queen Elizabeth II.
“The thoughts of all Canadians are with her and the entire Royal as they mourn this significant loss.”
Australia’s Prime Minister Scott Morrison said in a statement: “Through his service to the Commonwealth he presided as patron or president of nearly 50 organisations in Australia.
“Given his own service, Prince Philip also had a strong connection with the Australian Defence Force.
“For 65 years, The Duke of Edinburgh’s Award scheme has encouraged over 775,000 young Australians to explore their leadership potential.
“Forty thousand young Australians are currently participating in the program.
“Australians send our love and deepest condolences to her Majesty and all the Royal.”
Indian Prime Minister Narendra Modi, said: “He had a distinguished career in the military and was at the forefront of many community service initiatives. May his soul rest in peace.”
Imran Khan, Pakistan’s prime minister, tweeted: “Britain has lost a wise elder who was imbued with a unique spirit of public service.
“His role in promoting Pakistan-UK relations will always be remembered.”
A look back at Philip’s difficult childhood, his first meeting with the Queen and a life of service
Jacinda Ardern, New Zealand’s prime minister, posted a statement on Instagram saying: “Our thoughts are with Her Majesty The Queen at this profoundly sad time.
“On behalf of the New Zealand people and the Government, I would like to express my sincere condolences to Her Majesty and to all the Royal.”
A statement from the Kremlin said Vladimir Putin had sent a telegram to the Queen expressing “deep condolences”.
“Many important events in the modern history of your country are associated with the name of His Royal Highness,” Mr Putin wrote.
“He rightfully enjoyed respect among the British and international authority.”
In expressing his “sincere condolences”, French President Emmanuel Macron said the Duke had “lived an exemplary life defined by bravery, a sense of duty and commitment to the youth and the environment”.
German Chancellor Angela Merkel tweeted: “I am deeply saddened by the death of Prince Philip. His friendship with Germany, his straightforwardness and his sense of duty will not be forgotten.”
Italian President Sergio Mattarella praised a “figure who for over 70 years offered, with exemplary dedication, his service to the Crown and the United Kingdom, accompanying the evolution of his country with an open and innovative spirit”.
Turkish president Recep Tayyip Erdogan tweeted: “Upon the passing of The Prince Philip, Duke of Edinburgh, spouse of Queen Elizabeth II, I convey my deepest condolences on behalf of my country and the Turkish nation.
“I share the sorrow of the Royal and the people of the United Kingdom.”
Former US president George W Bush has praised the Duke of Edinburgh’s devotion to worthy causes and to others.
In a statement issued on behalf of himself and his wife Laura, Mr Bush said: “He represented the United Kingdom with dignity and brought boundless strength and support to the sovereign.
“Laura and I are fortunate to have enjoyed the charm and wit of his company, and we know how much he will be missed.”
With former US President George W Bush and First Lady Laura in 2003. Pic: AP
“We remember the duke for all of this and above all for his steadfast support for Her Majesty the Queen.
“Not just as her consort, by her side every day of her reign, but as her husband, her ‘strength and stay’, of more than 70 years.”