The UN World Food Programme (WFP) on Monday appealed for 460 million dollars to feed 9.6 million hungry people affected by drought and high food prices in Ethiopia through to March next year.
"The Horn of Africa region is facing the worst humanitarian crisis since 1984, and Ethiopia is caught in the middle," said WFP Executive Director Josette Sheeran in a statement issued in Nairobi.
"We know what needs to be done - we just need the funds to go out and do our job, protecting the hungry."
The world's largest humanitarian lifeline said around a quarter of those in need, some two million people, live in the arid Somali Region of Ethiopia where it has not rained for three years.
The communities in the region have already lost half of their cattle herds. People are skipping meals and parents are pulling children out of school so that they can help to beg in towns or scour the countryside for food.
"Millions of people are in extreme distress and urgently need food and nutrition," said Sheeran.
WFP said it was also facing a similar humanitarian challenge in neighbouring Somalia, where 3.25 million people, almost half the population, have been affected by drought, high food prices and conflict.
Ninety per cent of WFP's food deliveries to Somalia arrive by sea, but attacks by pirates are disrupting supply lines and discouraging ship owners from making the journey.
A Canadian naval vessel that has been escorting ships carrying humanitarian aid would withdraw its support on September 27, and no nation has yet volunteered to take over this protective role.