Close to 16 million people face hunger in southern Africa because of a drought made possible by unfavourable weather patterns.
The number may increase to 50,000, the United Nations World Food Programme has said.
“El Nino is progressing toward a potential regional emergency requiring a coordinated response,” the WFP said.
In January, the agency said 14 million people in the region faced severe hunger.
The figures exclude South Africa, where the government warned some 2.7 million households would be affected.
For the region as whole, WFP said many areas had recorded their lowest rainfall in 35 years between October 2015 and January 2016, a key planting window.
The drought conditions are also hurting livestock, which is a major source of wealth for many rural households in the region.
“Limited water availability and poor pasture are worsening livestock conditions. The number of livestock deaths is already increasing in parts of Botswana, Lesotho, Namibia, South Africa, Swaziland and Zimbabwe.”