ROBERT MUGABE used the recently held UN world food conference in Rome to accuse Britain and its Western allies of trying to topple him through “illegal regime change” by crippling Zimbabwe economically.

There was also serious criticism from a more authoritative source when Jacques Diouf, the head of the UN Food and Agriculture Organisation, accused the West of getting its priorities wrong, worrying about climate change, cars and biofuels at the expense of feeding the poor. Mr Diouf said: “Nobody understands how $11 billion to $12 billion a year of subsidies in 2006 have had the effect of diverting 100 million tonnes of cereals from human consumption, mostly to satisfy a thirst for fuel for vehicles.”

Mr Diouf called for £15 billion a year to be spent on giving 862 million hungry people “the right to food”.

He said that the amount spent on food aid for the Third World had more than halved in real terms, from £4 billion in 1980 to £1.7 billion in 2004. Ed Schafer, the US Agriculture Secretary, said that biofuels were responsible for only 2 to 3 per cent of the predicted 43 per cent rise in food prices this year.

Other participants said that biofuels accounted for 15 to 30 per cent of the increases. President Mubarak of Egypt called for “agricultural crops to be used as food for human beings, not as fuel for engines”.

The biofuel row threatens to derail attempts to find a consensus at the summit because the United States, Canada and Brazil all have sizeable biofuel industries. The President of Brazil, Lula da Silva, said that blaming biofuel for soaring food prices was an oversimplification.

The summit opened with a call from Ban Ki Moon, the UN Secretary- General, for world food production to rise by 50 per cent by 2030 to meet growing demand. He called for lower export restrictions and import tariffs with immediate effect.

The conference has been overshadowed by the row over Mr Mugabe and by the presence of President Ahmadinejad of Iran, who has used his visit to Rome to attack what he called Israel’s “criminal and terrorist Zionist regime”. Mr Mugabe said that Britain had “mobilised its friends and allies in Europe, North America, Australia and New Zealand to impose illegal economic sanctions against Zimbabwe. All this has been done to cripple Zimbabwe’s economy and thereby effect illegal regime change in our country.” He blamed the fact that millions of Zimbabweans were facing starvation on the sanctions, as well as on climate change and fuel prices.

Mr Mugabe said Britain and its allies had channelled funds through nongovernmental organisations to opposition parties, which were “the creation of the West”, thus using food aid as a political weapon. The Zimbabwean leader said that his country had democratised land ownership over the past decade and 300,000 Zimbabweans were now the proud owners of land previously owned by 4,000 white farmers, “mainly of British stock”. This had been welcomed by “the vast majority of our people” but had “elicited wrath from our former colonial masters”. He was applauded politely but reproved by the chairman for running over the allotted five minutes.

Douglas Alexander, Britain’s International Development Minister, retorted that Mr Mugabe himself was to blame for ruining Zimbabwe, once the breadbasket of southern Africa. In his speech Mr Ahmadinejad alleged that unnamed profiteering forces were driving up oil prices to further their geopolitical aims. “While the growth of consumption is lower than that of production and the market is full of oil, prices continue to rise and this situation is completely manipulated,” he told the summit.

Mr Ahmadinejad had asked for an audience with Pope Benedict XVI but the Vatican said all such requests had been turned down. It said the Pope was unable to meet various leaders “because of the number of requests, the limited time available, and prior commitments”.

Neither Mr Mugabe nor Mr Ahmadenijad was invited to a banquet hosted by the Italian Prime Minister Silvio Berlusconi.