Mr Annan spared the blushes of most African leaders.
Former UN Secretary General Kofi Annan has said Africa faces an aid shortfall of $40bn (£26bn).
Speaking at the launch of a new report by the Africa Commission, he said African leaders had to live up to their promises on good governance.
Mr Annan also chastised the industrialised world for failing to meet the pledges they gave to double aid by 2010.
The current rate of increase would not hit this goal, he said.
"Our reports show that at the present rate of growth the G8's pledge to double assistance to Africa by 2010 will not be fulfilled," Mr Annan said at the launch of the report in London.
But the report, written by the panel set up to monitor progress towards the Africa Commission's goals, failed to name which industrialised countries were not coming up with the money, the BBC's Africa analyst Martin Plaut says.
The UK's Secretary of State for International Development Douglas Alexander said that Britain was "delivering on its promises to the world's poor".
"By 2010 we will have given £12bn new aid to developing countries, with half of this - more than £6bn - going to Africa," he said.
Mr Annan also said that Africa had to do "much, much more" to do to keep its promise to improve governance.
The cost of food will not be measured in the price of wheat and rice, but in the rising number of infant and child deaths across Africa
He singled out Zimbabwe and Darfur as two crises that had to be addressed, and called on African leaders to act.
"The resolution of these crises will require greater and more consistent efforts by the African Union as well as leadership from individual African governments and the international community as a whole," he said.
But again Mr Annan spared the blushes of most African leaders, our correspondent says, refraining from naming and shaming those who failed to live up to their commitments to democracy.
The commission was set up in 2005 by then UK Prime Minister Tony Blair with the idea that African countries would improve their democratic credentials, while the west would double aid by 2010.
Mr Annan also warned that the global food crisis threatens to reverse what he said were many of Africa's hard-fought gains.
"With 100 million people on the brink of abject poverty, the cost of food will not be measured in the price of wheat and rice, but in the rising number of infant and child deaths across Africa," he said.