Washington- Efforts by industrialized countries to reduce their dependence on foreign energy sources and cut climate-changing emissions has prompted a strong backlash from some developing nations dealing with a worsening food crisis.

The problem lies in bio-fuels, an alternative source of energy that is often made from food crops. The World Bank last week said that a boost in bio-fuels production was largely to blame for an 83- per-cent increase in food prices over the last three years.

High food prices, which the development bank says are unlikely to fall dramatically before 2015, have prompted severe food shortages and even riots in poorer countries.

Some ministers attending the World Bank's annual spring meeting on Sunday expressed outrage - publicly and privately - that richer nations were feeding their petrol needs while people in the developing world were starving.

"In a world where there is hunger and poverty, there is no policy justification for diverting food crops towards bio-fuels," Indian Finance Minister P Chidambaram said in a statement, calling for an end to all subsidies for food-derived fuels.

"Converting food into fuel is neither good policy for the poor nor for the environment."

Dominique Strauss-Kahn, head of the World Bank's sister-lender, the International Monetary Fund, said that many ministers expressed similar concerns to him privately over the weekend - some labelling food-to-fuel production a "crisis of humanity."

Both Strauss-Kahn and World Bank President Robert Zoellick have said that the current food crisis threatens to destroy the gains made since 2000 in reducing poverty around the world.

Hundreds of thousands of people are threatened with starvation, Strauss-Kahn said Thursday, while the World Bank estimates that 33 nations could face social unrest from food shortages.

Haiti's legislature sacked the government on Saturday after at least five people were killed this month in food riots.

Zoellick, while not calling for a halt in bio-fuels production, said that industrial nations thirsting for energy had even more reason to meet an urgent call for 500 million dollars in food aid by the end of the month.

Advanced economies, though recognizing the threat that high food prices pose to poor countries, have been slow to address the crisis' link to their own energy needs.

US Treasury Secretary Henry Paulson said that bio-fuels did not come up Friday during a meeting of finance ministers from the world's top seven industrialized nations, though they did express concern over the food price surge.

The United States and Brazil are the world's largest producers of ethanol - a fuel for cars that the Bush administration has made a key element of its bid to cut reliance on oil from foreign and sometimes hostile countries.

US ethanol producers use chiefly maize, while Brazil's production relies on sugar cane as a raw material. Other methods used in various countries use edible oils to produce diesel fuel. In the United States, soya-based bio-diesel is a fast-growing product.

Bio-fuels have been hailed as an answer to climate change - a clean, renewable energy alternative that can reduce industrial nations' emissions of greenhouse gases, which are blamed for global warming.

That prospect creates a paradox for developing countries struggling with high food prices but also fearful of the potentially devastating consequences of climate change.

The World Bank has been quick to acknowledge differences in how various bio-fuels are produced: some are more energy efficient than others.

Most scientists consider Brazil's sugar-cane ethanol a very energy-efficient process, while both Zoellick and Strauss-Kahn touted promising research into "second-generation" bio-fuels that would use non-food sources such as grass or wood chips.

US production of maize-based ethanol is highly subsidized and has been criticized by a growing number of scientists as only slightly less energy intensive than oil.

In a report last week on food prices, the World Bank said that US ethanol ate up nearly all of the increased global maize production from 2004-07, when the crop's prices rose most sharply.

Wheat, soy and palm oil prices have all been hit by increased bio- fuel production, the World Bank said.

"While many are worried about filling their gas tanks, many others around the world are struggling to fill their stomachs," Zoellick said Thursday. (dpa)