LONDON — U.S. Department of Agriculture figures reveal that a quarter of U.S. cereals grown in 2009 went to biofuel, turning cheap food into expensive fuel. This pushes up food prices and damages the environment, yet President Barack Obama promised "continued investment in advanced biofuels" in his recent State of the Union address.

A paper on the 2007-2008 food crisis by the World Bank Development Prospect Group, leaked in 2008, said U.S. and European Union biofuel production was responsible for 70 to 75 percent of the price rises — against 3 percent admitted by the U.S. Department of Agriculture.

These subsidies are about political pandering, not cutting greenhouse gases. But despite a backlash against biofuels in 2008, they have now fallen off the international agenda.