JOHANNESBURG • Nearly one million children across eastern and southern Africa are suffering from "severe acute malnutrition" after two years of drought and the strongest El Nino in 50 years, United Nations children's agency Unicef said.

Children in the region face food and water shortages, with rising prices worsening the situation as families are forced to skip meals and sell belongings.

"The El Nino weather phenomenon will wane, but the cost to children - many who were already living from hand to mouth - will be felt for years to come," said Unicef regional director Leila Gharagozloo-Pakkala.

"Governments are responding with available resources, but this is an unprecedented situation. Children's survival is dependent on action taken today."

Lesotho, Zimbabwe and most of South Africa have declared drought emergencies, while in Ethiopia, the number of people in need of food assistance is expected to rise from 10 million to 18 million this year.

Malawi is facing its worst food crisis in nine years, with 2.8 million people - more than 15 per cent of the population - at risk of hunger, and severe acute malnutrition has doubled in only two months.

"Severe acute malnutrition" is defined as extreme hunger, causing a very low weight-to-height ratio, visible wasting or fluid retention.

Last month, the UN's World Food Programme (WFP) said 14 million people across southern Africa faced going hungry after the prolonged drought wrecked harvests.

The WFP said the cost of maize, also called corn, in Malawi was 73 per cent higher than average. South Africa will import half its average maize crop after 2015 was declared the driest year in more than a century.

The agency is running humanitarian appeals calling for US$87 million (S$122 million) for Ethiopia, US$26 million for Angola and US$15 million for Somalia.

AGENCE FRANCE-PRESSE