Food security and the rapid rise in food prices make up the “elephant in the room” that politicians must face up to quickly, according to the government’s new chief scientific adviser.

In his first major speech since taking over, Professor John Beddington said the global rush to grow biofuels was compounding the problem, and cutting down rainforest to produce biofuel crops was “profoundly stupid”.

He told the Govnet Sustainable Development UK Conference in Westminster: “There is progress on climate change. But out there is another major problem. It is very hard to imagine how we can see a world growing enough crops to produce renewable energy and at the same time meet the enormous increase in the demand for food which is quite properly going to happen as we alleviate poverty.”