Three U.N. food agencies have urged governments to take quick action to curb rising prices of corn, wheat, and soybeans. They fear a repeat of the 2007-2008 food crisis.
The sharp rise in food prices in recent months threatens to make life even harder for millions of people around the world, especially in poor countries.
''The situation is very serious right now," Jose Cuesta, a senior economist with The World Bank Group, warned.
"We have seen that food prices have increased sharply in the month of July, especially for soy beans and maize, which are right now at an all-time high," he said. "Also the price of wheat is very high, has increased about 25 percent in the same month."
A prolonged drought in the United States, which is the No. 1 exporter of corn, wheat, and soybeans, has helped drive up commodity prices.
The U.N. said global food prices rose 6 percent in July. It's even begun to affect donations to food banks.
"We're beginning to see some of the impacts of the drought here in Washington state, so many of the products that would typically be donated to a local food bank are now suddenly being diverted," Linda Nageotte, president of the food distribution group Food Lifeline, said.
U.N. officials said countries should reduce ethanol production requirements when food supplies become scarce.
Livestock farmers in the United States have demanded the government relax biofuel production quotas because corn feed is becoming so expensive.
Forty percent of the U.S. corn crop goes to ethanol production.