"There were some serious promises made. The cheques were signed but as you know, politicians like signing cheques but they don't like cashing them," Bono told reporters in Davos.
As a regular on the world business and aid circuit, Bono is campaigning for richer countries to forgive African nations' debt and help fund their future.
At a meeting in 2005, the G8 group of industrialised nations agreed to cancel the debts of 18 low-income countries and pledged to double African aid to about USD $47 billion by 2010.
"Two years on, it's time to take the temperature," Bono said. "If those promises are not kept ... it will make a generation of cynics. I don't believe that's going to happen, I am optimistic we're going to get through this."
Bono said debt cancellation programs had already opened the way for 20 million African children to go to school but there was still "lots, lots, lots to do."
He pointed to the situation in Liberia, where President Ellen Johnson-Sirleaf is working to attract aid and get relief for the country's USD $3.7 billion debt, racked up during years of conflict fuelled by money from the sale of diamonds.
"She is trying quell civil unrest and she's got this ridiculous debt hanging over her head because of two corrupt leaders before and that is just not right," Bono said.
