Campaigning rocker Bono confronted US President George W Bush after discovering the United States has held back aid money promised to Africa.

Only a fraction of the cash in the Millennium Challenge Account - a US initiative for Africa set up in 2004 - has found it's way to the continent.

And Bono insists he went straight to the top for answers.

He says, "I'm p**sed. I'm mad , in fact, that not more has happened. But still, more has happened than any could have imagined from them. Even though $400,000 is the figure so far, over $2 billion has been set aside for Africa.

"We have had a heated debate about this, myself and the president. Funnily enough, he was almost as p**sed as I was.

"He said there was no excuse. But it's clear they had a lot on their mind. After 9/11 and entering into the war, some desks got very overcrowded. It's not an excuse that I'm accepting, but I do believe they will put it right.

"Even the most staunch critics will concede that the president has tripled aid to Africa."