Poor farmers in Niger, Chad and northeastern Mali will likely need food aid until the early harvests of August.
The United Nations says poor rains in Africa's Sahelian region mean harvests for staple food crops will likely be one-third lower than normal.
Poor rains from the end of September to the end of October are bringing below average harvests in Niger, northern Nigeria, central Chad and northeastern Mali and Burkina Faso.
Thomas Yanga is the West Africa Regional Director for the United Nations World Food Program.
"We anticipate increased prices and high-rates of malnutrition, which could combine to increased food assistance needs in the 2010 lean season for several million people in the sub-region," said Thomas Yanga.
The UN's Food and Agriculture Organization estimates that aggregate cereal production in Niger will be just over 3.5 million tons this year. That is 26 percent below last year's harvest.
Millet prices in Niger's capital, Niamey, are 42 percent higher than 2007. Severe pest infestation and poor rains this year have led to a 34 percent decline in cowpeas, which are the main source of income for small-scale farmers.
"We are, therefore, getting prepared for a new crisis on the food security front in eastern Sahel, where malnutrition rates are already above emergency thresholds," he said.
In Chad, the sorghum harvest is down 22 percent and millet is down 34 percent compared to last year. Millet prices in the capital, Ndjamena, are 72 percent higher than 2007.
Jean-Luc Siblot heads World Food Program operations in Chad.
"There, we know that we have already a structural malnutrition problem, which is going on for years and years and years," he said. "This structural malnutrition, under-nutrition problem will be doubled by this problem, due to this decrease in agricultural production."
The UN estimates that the need for food assistance will be higher than normal for pastoralist communities in the eastern Sahel between January and June of next year. Poor farmers in Niger, Chad and northeastern Mali will likely need food aid until the early harvests of August.