Barack Obama: Muhammad Ali was The Greatest. Period.

US President Barack Obama has paid a glowing tribute to Muhammad Ali, saying the boxer "shook up the world and the world is better for it".

Mr Obama revealed he keeps a pair of Ali's gloves in a private study at the White House and said we are fortunate that "the Greatest chose to grace our time".

In a statement, he said:

"Muhammad Ali was The Greatest. Period. If you just asked him, he'd tell you. He'd tell you he was the double greatest; that he'd 'handcuffed lightning, thrown thunder into jail'

"Like everyone else on the planet, Michelle and I mourn his passing. But we're also grateful to God for how fortunate we are to have known him, if just for a while; for how fortunate we all are that The Greatest chose to grace our time.

"'I am America,' he once declared. 'I am the part you won't recognise. But get used to me - black, confident, cocky; my name, not yours; my religion, not yours; my goals, my own. Get used to me'.

"We watched a hero light a torch, and fight his greatest fight of all on the world stage once again; a battle against the disease that ravaged his body, but couldn't take the spark from his eyes.

"Muhammad Ali shook up the world. And the world is better for it. We are all better for it. Michelle and I send our deepest condolences to his family, and we pray that the greatest fighter of them all finally rests in peace."