Sudanese-born billionaire Mo Ibrahim on Saturday castigated Africa's ageing leaders for crowding out young blood.
The philanthropist said the average age of leaders on the African continent was around 60 years, yet half of the population was under the age of 19.
Speaking at a lecture in honour of South Arica's first black president Nelson Mandela, the businessman drew comparisons between African and American leaders.
"(Barack) Obama became president when he was 47 years old, actually Bill Clinton beat him, he became president when he was 46 years old.
"People in their 40s are being elected to run a country which is not only the greatest superpower, but has a GDP ... of 15-trillion dollars a year -- 15 times the total economy of Africa."
"And here we have somebody in a neighbouring country, at 90 about to start a new term. What's wrong with us?" Ibrahim said, alluding to Zimbabwe's President Robert Mugabe, who at 89 was last month re-elected in disputed polls that extended his 33-year rule by a fresh five-year term.
Ibrahim said that had Obama's father taken him back to Kenya when he was still a boy, "where would he be today? My guess, he would never (have) been president of Kenya."
He urged Africa to create space for young people to help in running and developing the continent.
"That is the challenge we need to think of," said Ibrahim, who is in his sixties.
The telecoms tycoon has set up the Ibrahim Prize for Achievement in African Leadership -- the world's biggest individual prize -- awarded to a democratically-elected African leader who has served their mandated term and left office in the last three years.
Last year it was not awarded for a third time in four years as no suitable candidates were found.
Launched in 2006, it carries a $5 million prize paid over 10 years and $200,000 annually for life from then on, with a further $200,000 per year available for 10 years for good causes backed by the winner.
The inaugural prize went to former president Joaquim Chissano of Mozambique in 2007 and Botswana's ex-president Festus Mogae won in 2008.
Former Cape Verde president Pedro Pires won the 2011 prize.