At issue is the impact of grain-based biofuels on food prices - now at their highest levels since the 1970s - and a related wrangle over bioenergy subsidies. But there is also, increasingly, a rethink of how "green", or eco-friendly, biofuel really is.
"There is no agreement on the impact of grain-based biofuel on food prices," Alexander Müller, Assistant Director-General of the UN Food and Agriculture Organisation (FAO), told IRIN. Various studies and think-tanks have come up with estimates of the impact of biofuel on food prices that range from 10 percent to 60 percent.