Tributes have been paid to Republican senator John McCain after he died at the age of 81 following a battle with brain cancer.
Below are some of the reactions to the death of the veteran politician who stood against Barack Obama in 2008.
:: Theresa May
"John McCain was a great statesman, who embodied the idea of service over self. It was an honour to call him a friend of the UK. My deepest sympathies go to his family, and the American people."
:: Donald Trump
"My deepest sympathies and respect go out to the family of Senator John McCain," he said. "Our hearts and prayers are with you!"
:: Melania Trump
On Twitter, the US first lady wrote: "Our thoughts, prayers and deepest sympathy to the McCain Family. Thank you Senator McCain for your service to the nation."
:: Mike Pence
"Karen and I send our deepest condolences to Cindy and the entire McCain family on the passing of Senator John McCain," the vice president said. "We honour his lifetime of service to this nation in our military and in public life. His family and friends will be in our prayers. God bless John McCain."
:: James Mattis
The secretary of defence said the US had "lost a man who steadfastly represented the best ideals of our country".
:: Barack Obama
The former president said: "John McCain and I were members of different generations, came from completely different backgrounds, and competed at the highest level of politics.
"But we shared, for all our differences, a fidelity to something higher – the ideals for which generations of Americans and immigrants alike have fought, marched, and sacrificed. We saw our political battles, even, as a privilege, something noble, an opportunity to serve as stewards of those high ideals at home, and to advance them around the world.
"We saw this country as a place where anything is possible – and citizenship as our patriotic obligation to ensure it forever remains that way."
:: Joe Biden
"John McCain's life is proof that some truths are timeless. Character. Courage. Integrity. Honour. A life lived embodying those truths casts a long, long shadow," the former vice president said. "John McCain will cast a long shadow. His impact on America hasn't ended. Not even close. It will go on for many years to come."
He added: "America will miss John McCain. The world will miss John McCain. And I will miss him dearly."
:: George W Bush
The former president said: "Some lives are so vivid, it is difficult to imagine them ended. Some voices are so vibrant, it is hard to think of them stilled. John McCain was a man of deep conviction and a patriot of the highest order. He was a public servant in the finest traditions of our country. And to me, he was a friend whom I'll deeply miss. Laura and I send our heartfelt sympathies to Cindy and the entire McCain family, and our thanks to God for the life of John McCain."
:: Sarah Palin
Mr McCain's 2008 running mate said: "Today we lost an American original. Sen. John McCain was a maverick and a fighter, never afraid to stand for his beliefs. John never took the easy path in life – and through sacrifice and suffering he inspired others to serve something greater than self.
"John McCain was my friend. I will remember the good times. My family and I send prayers for Cindy and the McCain family."
:: Bill and Hillary Clinton
In a joint statement, the former US leader and ex-secretary of state said: "Senator John McCain believed that every citizen has a responsibility to make something of the freedoms given by our constitution, and from his heroic service in the navy to his 35 years in Congress, he lived by his creed every day.
"He was a skilled, tough politician, as well as a trusted colleague alongside whom Hillary was honoured to serve in the Senate.
"He frequently put partisanship aside to do what he thought was best for the country, and was never afraid to break the mould if it was the right thing to do. I will always be especially grateful for his leadership in our successful efforts to normalise relations with Vietnam."
:: Paul Ryan
The house speaker said: "This is a sad day for the United States. Our country has lost a decorated war hero and statesman. John McCain was a giant of our time not just for the things he achieved, but for who he was and what he fought for all his life.
"John put principle before politics. He put country before self. He was one of the most courageous men of the century. He will always be listed among freedom's most gallant and faithful servants. Our hearts are with his wife, Cindy, his children, and his grandchildren. This Congress, this country, mourn with them."
:: Jimmy Carter
"John McCain was a man of honour, a true patriot in the best sense of the word," said the former president. "Americans will be forever grateful for his heroic military service and for his steadfast integrity as a member of the United States Senate."
:: Justin Trudeau
The Canadian prime minister said: "Senator John McCain was an American patriot and hero whose sacrifices for his country, and lifetime of public service, were an inspiration to millions. Canadians join Americans tonight in celebrating his life and mourning his passing."
:: Benjamin Netanyahu
The prime minister of Israel said: "I am deeply saddened by the passing of John McCain, a great American patriot and a great supporter of Israel. I will always treasure the constant friendship he showed to the people of Israel and to me personally.
"His support for Israel never wavered. It sprang from his belief in democracy and freedom. The State of Israel salutes John McCain."
:: Tony Blair
The former prime minister described "a good friend, a gifted politician and an even better man".
He said: "An exceptional human being, he was unafraid of standing up strong and resolute in defence of the principles he believed in.
"He was also great company – witty, fiery, always interesting and stimulating with a high intelligence and deep humanity.
"In a world searching for examples of political integrity he was such an example and a supreme one at that."
:: UK ambassador
Sir Kim Darroch, the UK ambassador to the US said: "Deeply saddened to hear of John McCain's passing. Across my career, I had the privilege of meeting him several times.
"He was wise, principled, gracious, and humble, and a great friend of the United Kingdom. America has lost a true hero and statesman."