This file photo taken on September 10, 1974 shows former world heavyweight champion Muhammad Ali posing in Paris. (AFP)
Former US president Bill Clinton said on Saturday that he and his wife, Democratic presidential hopeful Hillary Clinton, were "saddened" by the passing of Muhammad Ali.
"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," read a statement from the former president's office.
"We watched him grow from the brash self-confidence of youth and success into a manhood full of religious and political convictions that led him to make tough choices and live with the consequences," he said.
Ali was "courageous in the ring, inspiring to the young, compassionate to those in need, and strong and good-humored in bearing the burden of his own health challenges."
Bill Clinton said he was "honored" to have awarded Ali the Presidential Citizens Medal at the White House in January 2001, just before leaving office.
"Through triumph and trials," Clinton said, Ali "became even greater than his legend."
The 74-year-old sports hero, who had been battling Parkinson's disease for decades, DIED in a hospital in Phoenix, Arizona where he had been admitted earlier suffering from respiratory problems.