Cargill's new chief executive has warned that the boom in renewable fuels could be derailed by a succession of poor harvests, intensifying upward pressure on food costs as land is devoted to energy-related production.

Gregory Page, a 33-year veteran of the world's largest agribusiness group, reiterated his concern thatbiofuel mandates and other incentives will distort the allocation of land, with the potential to create food shortages around the world in the wake of "weather-related crop problems".