Germany:Bono and Bob Geldof have accused leaders of the world's wealthiest countries of breaking aid promises made to Africa two years ago.
Of the additional $25 billion (€18.39 billion) in African aid that G8 leaders promised to donate by the end of the decade, some $22.2 billion is outstanding.
On average, G8 countries have given only half of the funds needed to reach their 2010 target; this year just a third of what is needed is in the pipeline.
"Why are politicians not doing what they promised and creating another wave of cynicism among the young population?" asked Geldof.
He was speaking at the presentation of the annual report by the advocacy group for Africa, Data (Debt, Aids, Trade, Africa).
The Data report produced evidence that debt cancellation and aid increases had put 20 million more African children into schools between 2000 and 2004, but that future aid work was threatened if countries fall behind in aid payments.
Japan and Britain were on track with their aid promises, the report found, while Germany and France would need to give an extra $869 million and $1.5 billion respectively to get back on track this year. Italy was the worst aid offender, having cut aid by 30 per cent.
U2 lead singer Bono expressed concern that, without a renewed aid deal, there could be violence on the streets of German cities during next month's G8 summit in the Baltic coast resort of Heiligendamm.
"People are very angry. There are a lot of people who would rather this failed because they don't think much of our extraordinary discourse," he said. "I believe there is a certain moral compass in the German people that the world needs to see. That's why this G8 is so important to us: because it's in Germany. People believe Germans when they agree to something and when Germany breaks its agreement everyone else will abandon ship."