WASHINGTON (AP) — Former President Bill Clinton is warning farmers not to use so much corn for ethanol fuel that it raises food prices and causes riots in other countries.

Clinton told farmers and Agriculture Department employees that he believes producing biofuels such as corn-based ethanol is important for reducing U.S. dependence on foreign oil. But he says farmers also should look beyond domestic production and consider the needs of developing countries.

Clinton spoke Thursday at the department’s annual Agricultural Outlook Forum. His foundation has worked to develop agribusiness in African countries such as Malawi and Rwanda.