World leaders on Friday pledged to commit $20bn over three years for a “food security initiative” to develop agriculture in poor countries, but aid agencies responded with scepticism, pointing to a chain of broken promises and a habit of switching around existing budgets.

The Group of Eight summit of rich countries in L’Aquila, Italy, had aimed to pledge $15bn (€10.8bn, £9.3bn). Ministers described how a last whip-round before delegations left came up with an extra $5bn to make a bigger headline ­figure. “There is an urgent need for decisive action to free humankind from hunger and poverty,” said a joint statement of 40 heads of government and international organisations, including the G8.

How much of the promised money was new or how it would be managed remained unstated. Officials said a substantial amount of the $3.5bn promised by the US was a new allocation. UK officials candidly admitted that their pledge of $1.8bn had been reallocated to food and agriculture from other aid lines.

Even some of the eight African leaders present were left in the dark about the substance.

President Jacob Zuma of South Africa told reporters he did not know details. “It has not been discussed who will [administer it] and how,” he said. Diplomats said the World Bank would probably be the choice of the Obama administration.

SUMMIT DIARY

Final day

● Barack Obama, US president, on Friday warned Iran that the world will take “further steps” against Tehran if it fails to begin negotiating over its nuclear weapons programme later this year, writes James Blitz.

Mr Obama said the meeting of world leaders had never had any intention of imposing new sanctions on Iran, as some media reports suggested.

But he said world leaders would evaluate Iran’s stance at the G20 summit in Pitttsburgh in September.

● “The G8 is the earthquake, we are all citizens of L’Aquila,” said the opening banner of the anti-globalisation protest march on Friday, writes Giulia Segreti.

More than four thousand people took part, protesting both against the G8 and Silvio Berlusconi’s government.

● When Mr Berlusconi said a new G14 should replace the G8, he might have recalled the last time he championed a G14, writes Tom O’Sullivan.

That was back in 2000, when the lobby group was formed to give the wealthiest football clubs in Europe more control over the running of the sport.

The football G14 was disbanded last year. Mr Berlusconi will hope the same fate does not await his all-new version.

A history of broken pledges by rich countries has non-governmental organisations on their guard. The G8 pledge at Gleneagles four years ago to give $50bn in development aid by 2010, with half going to Africa, has left a gap of at least $15bn so far. The G8 does not say how it will make it up by next year.

“Much of this funding is recycled,” said Oxfam, an aid agency, giving the initiative a cautious welcome. “But the new money makes a downpayment on eliminating hunger. With a billion people facing hunger, more new money is still needed.”

The summit statement addressed the scepticism, declaring: “Commitments to increase overseas development aid must be fulfilled. The tendency of decreasing ODA and national financing to agriculture must be reversed.”

Born out of the surge in global food prices last year and the financial crisis hitting budgets of developing countries, the initiative is focused on helping smallholder farmers over the long term. But it promised not to take resources from emergency relief.

Josette Sheeran, head of the UN World Food Programme, which tackles both food emergencies and longer-term projects, said she has only 25 per cent of the budget needed this year for $6.4bn of assessed needs.

“Price pressure on the poorest people has not alleviated despite a fall from last year’s peaks in global prices,” Ms Sheeran pointed out, noting that in 80 per cent of countries food is more expensive than a year ago. “We are cutting rations.”

She called the new fund a “huge step forward”. From 1969 to 2004 the proportion of the world’s population suffering from hunger dropped from 30 per cent to 17 per cent. Now it is on the rise again. “We are reopening in countries we pulled out of,” Ms Sheeran said, naming Kyrgyzstan as an example.

Silvio Berlusconi, Italy’s billionaire prime minister, was stung by accusations last week that Italy had cut its aid budget, saying he would rectify the mistake. Despite that assurance, Marcello Fondi, a senior foreign ministry official, later disclosed that his ministry’s aid budget would fall by a further 10 per cent in 2010, according to Adrian Lovett, a spokesman for Save the Children.

Franco Frattini, foreign minister, told the FT that the $480m pledged by Italy for the food security fund would be new money.