Tributes for Muhammad Ali from around the globe Saturday demonstrated that the former world champion boxer transcended sport and inspired millions.
"Muhammad Ali was one of the greatest human beings I have ever met. No doubt he was one of the best people to have lived in this day and age," George Foreman, Ali's rival in the Rumble in the Jungle, said.
Ali, who had Parkinson's disease, died aged 74 after being admitted to a hospital in Phoenix, Arizona on Thursday suffering from a respiratory illness.
Daughter Hana Ali tweeted: "Our father was a "Humble Mountain!" And now he has gone home to God. God bless you daddy. YOU ARE THE LOVE OF MY LIFE!"
Former US President Bill Clinton said he and his wife Hillary were saddened to hear of the death of Ail.
"From the day he claimed the Olympic gold medal in 1960, boxing fans across the world knew they were seeing a blend of beauty and grace, speed and strength that may never be matched again," he said.
Ali was "courageous in the ring, inspiring to the young, compassionate to those in need, and strong and good-humoured in bearing the burden of his own health challenges," Clinton added.
Former heavyweight champion Mike Tyson tweeted: "God came for his champion. So long great one. Muhammad Ali, The Greatest. RIP."
Thomas Bach, the president of the International Olympic Committee (IOC), said of Ali, who also lit the cauldron at the 1996 Atlanta Games: "He was an athlete who touched the hearts of people across the globe, an athlete who was engaged beyond sport, an athlete who had the courage to give hope to so many suffering illness by lighting the Olympic cauldron and not hiding his own affliction.
"He was an athlete who fought for peace and tolerance - he was a true Olympian. Meeting him in person was an inspiration. He was a man who at the same time was so proud and yet so humble."
Among other boxing tributes, Floyd Mayweather, world champion boxer across five divisions, said: "There will never be another Muhammad Ali. The black community all around the world, black people all around the world, needed him. He was the voice for us. He's the voice for me to be where I'm at today."
Don King, who promoted the Ali-Foreman Rumble in the Jungle and the Ali-Joe Frazier Thrilla in Manila in 1975, told Fox News: "Ali will never die. He was a fighter for the people and to become a champion of the people he demonstrated the type of character he was.
"He had the fortitude, the inspiration, the motivation to stand up for what he believed in and to say what he means and mean what he said. He brought me into the sport of boxing - my first fight was Muhammad Ali."
Former world champion Lennox Lewis tweeted: "A giant among men, Ali displayed a greatness in talent, courage & conviction, that most of us will EVER be able to truly comprehend."
Philippine boxing icon Manny Pacquiao said: "We lost a giant today. Boxing benefited from Muhammad Ali's talents but not nearly as much as mankind benefited from his humanity."
Former Pakistan cricketer, turned politician Imran Khan said via Twitter: "Saddened to hear of Muhammad Ali's death - the greatest sportsman of all times. Ali had great talent, was highly intelligent & courageous.
"What set Ali apart from other great sportsmen & what I most admired him for was his refusal to compromise on his belief & value system."
British Prime Minister David Cameron said: "Muhammad Ali was not just a champion in the ring - he was a champion of civil rights, and a role model for so many people."
Malaysian Prime Minister Najib Razak tweeted: "The world lost more than just a legendary boxer. We lost the greatest of all time."
German football great Franz Beckenbauer said: "Very sad day. The GREATEST has gone."
Former German tennis champion Boris Becker quoted an Ali catchphrase in a tweet: "Float like a butterfly/sting like a bee " A GIANT among men #RIPALI."
Singer Madonna shared two pictures of herself with Ali on Instagram and wrote: "This Man. This King. This Hero. This Human! Words cannot express. He shook up the World! God Bless Him."
