World leaders agreed a radical shift in aid strategy today by surpassing expectations and pledging a $20 billion programme to help poor nations feed themselves.

The fund, which will include $1.8 billion from Britain's development budget, will be spent on agricultural development in Africa and other nations, a switch of priorities from the traditional practice of direct food aid.

Leaders had been expected to agree a $15 billion fund but more pledges came during the final session from other nations. It was not clear immediately what part of the programme was "new" aid money and how much had been taken from other parts of aid budgets.

But the plan drew a welcome from aid organisations at the G8 summit.

Gordon Brown said: "It is unacceptable that people are hungry in a world as fertile as ours. Not only does Africa have the ability to feed itself if things are done right. Eventually it could play an extra part in feeding the world."

The United States used the meeting of world leaders to push for a shift towards farm aid from food aid and will make $3.5 billion available to the 3-year programme. But African nations reminded the rich of the need to honour past commitments.

The United Nations says the number of malnourished people has risen over the past two years and is expected to top 1.02 billion this year, reversing a four-decade trend of declines.

"Food aid is necessary because we have people suffering from drought, from flood, from conflicts and what they want is immediate food to eat," Jacques Diouf, head of the UN's Food and Agriculture Organisation, said at the L'Aquila summit.

"But if we have to feed 1 billion hungry people, we have to help them produce their own food," he said.

G8 leaders promised in Gleneagles in 2005 to increase annual aid by $50 billion by 2010, half of which was meant for African countries. But aid bodies say some G8 countries have gone back on their word, especially this year's G8 host, Italy.

African leaders said they would voice their concerns, with Ethiopian premier Meles Zenawi saying: "The key message for us is to ask the G8 to live up to their commitments."

Besides Meles, the leaders of Algeria, Angola, Egypt, Libya, Nigeria, Senegal and South Africa joined their G8 counterparts to discuss food security and farming, and to push their demand for compensation for the ravages of climate change.

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