President John Mahama and his main contender in the 2016 elections, Nana Akufo-Addo, have joined a host of world leaders to console the family of boxing legend Mohammed Ali, who passed on Saturday.

The former world heavyweight boxing champion, one of the world's best-known sportsmen, died at a hospital in the US city of Phoenix, Arizona, after being admitted on Thursday.

He was suffering from a respiratory illness, a condition that was complicated by Parkinson's disease.

The funeral will take place in Ali's hometown of Louisville, Kentucky, his family said in a statement.

In a tweet, Mahama said: Sad to hear the passing of Muhammad Ali. He was our hero and truly 'the Greatest'.

On his part, the New Patriotic Party (NPP) flagbearer Nana Addo described Ali as “the greatest boxer of the modern era.”

He tweeted: Eloquent, brilliant, principled, and icon. The greatest boxer of the modern era. May he rest in perfect peace.

Ali's career ended with one-sided defeats by Larry Holmes in 1980 and Trevor Berbick in 1981, many thinking he should have retired long before.

He fought a total of 61 times as a professional, losing five times and winning 37 bouts by knockout.