But as food prices climb worldwide, there is a fear that development of biofuels could reduce the production of badly-needed basic foodstuffs.
Ethanol production is on course to account for some 30% of the US maize crop by 2010, dramatically curtailing the amount of land available for food crops.
The EU has meanwhile come under criticism for its target of getting 10% of road transport fuel from crops by 2020.
The head of the UN World Food Programme and the chief of the African Development Bank chief are among those attending the London meeting.
Opening a UN forum on the global impact of climate change on indigenous peoples, Mr Morales said that capitalism should be scrapped if the planet is to be saved from the effects of climate change.
"If we want to save our planet earth, we have a duty to put an end to the capitalist system," he said.
South Americans warn over biofuels
Bolivia's left-wing president said unbridled industrial development was responsible for the pillaging of natural resources.
But, he said, "some South American presidents who were talking about biofuels but did not understand what they were talking about".
The BBC's Daniel Schweimler says this is a clear reference to Brazilian President Luiz Inacio Lula da Silva, who says his country has enough land to grow food crops as well as plants to produce biofuels.
Last week, he rejected allegations that biofuels were responsible for the recent rise in global food prices.
And on Monday, Brazil announced a major joint venture in Ghana to grow sugar cane for bio-ethanol.
"In Ghana we are developing a project that will result in growing 27,000 hectares (of sugar cane) for the production of 150 million litres of ethanol per year that are destined for the Swedish market," said President Lula, who was in Accra for the occasion.
Industrialised countries want to use a higher percentage of biofuels
For his part, Peru's President Garcia said the demand for biofuels was putting world food production under threat.
Just over 40% of Peruvians - some 12 million people - live below the poverty line and have been hit hard by the soaring cost of basic foodstuffs.
The global prices of wheat, rice and maize have nearly doubled in the past year, while milk and meat have more than doubled in price in some countries.
Such rises, combined with high oil prices, are causing increasing political instability in less developed countries across the world.
Food riots earlier this month in Haiti, which is highly reliant on imports of food and fuel, led to the deaths of at least six people, including a UN peacekeeper.
There has also been unrest in Burkina Faso, Cameroon, Egypt, Indonesia, Ivory Coast, Mauritania, Mozambique and Senegal.
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