US first lady Michelle Obama holds up a carrot as she gardens during a community service project at Vhuthilo Community Center in Soweto township, Johannesburg, South Africa, June 22, 2011. [Photo/Agencies]

JOHANNESBURG - Michelle Obama says leadership isn't limited to age or status in life and that the world is looking to its young people to be the next generation of problem-solvers.

The US first lady delivered that message Wednesday in Johannesburg, South Africa, during a keynote speech to an American-sponsored forum of young women leaders from the continent.

Sixty percent of Africa's population is under age 25. And in South Africa, two-thirds of its people are younger than 30.

Mrs. Obama urged her listeners to be the ones who banish hunger and end HIV/AIDS.

She spoke at the Regina Mundi Church in Soweto township, which was a religious hub and sanctuary during the anti-apartheid uprisings 35 years ago.