"We want to discuss this not with passion but rationality and not from the European point of view".

His comments follow a week of protests in Brazil and Europe against fuels derived from food crops and their supposed environmental and social benefits.

The growing criticism has placed Brazil at the centre of the global biofuels debate. The country has enjoyed an agricultural export boom, which has seen it become the world's largest exporter of ethanol -- derived from sugar cane.

Critics say the increased production of crops for ethanol and biodiesel, which is derived from oil seeds, competes with for land with food crops.

In Brazil, they say it is also pushing cattle ranchers and farmers further north and contributing to the destruction of the Amazon rainforest.

Competitors and critics have tried to link several leading Brazilian farm exports, from beef to soybeans, with environmental destruction and poor working conditions.

"Brazil is prepared for this debate. I and my government are ready to travel around the world," Lula said.

Brazil has repeatedly argued that it has plenty of unused land to plant crops for biofuels and that current production was still too small to affect food prices.

Lula, a former union leader, rebuffed accusations by Jean Ziegler, UN special rapporteur for the right to food. Ziegler this week called biofuels a "crime against humanity," though he referred mainly to US ethanol derived from corn.

"The real crime against humanity is to discredit biofuels a priori and condemn food-starved and energy-starved countries to dependence and insecurity," Lula said at a conference of the United Nation's Food and Agriculture Organization in Brasilia.

Some of Brazil's neighbours, led by oil-rich Venezuela, warned this week that biofuels could increase malnutrition in Latin America.

Lula said he was "shocked" that biofuel critics failed to mention the impact that high oil prices had on food production costs, such fertilizers. "It's always easier to hide economic and political interests behind supposed social and environmental interests," he said.

The European Union's environment chief said on Tuesday that biofuels, which Brazil hopes to export to the EU, now must meet social and environmental criteria. Scientists from the European Environment Agency urged the 27-nation bloc to drop its 10 percent biofuel target for road-transport fuels.