The United Nations appealed for $426 million to help victims of drought in Horn of Africa, where more than 40 percent of people are undernourished and thousands have died because of complications due to hunger.

Jan Egeland, the U.N. undersecretary-general for humanitarian affairs, launched the appeal on Friday to help 8 million people at severe risk of starvation in Kenya, Ethiopia, Eritrea, Somalia and Djibouti.

"Millions of people are threatened with starvation following the recent severe drought," he said. He estimated that "thousands, perhaps tens of thousands" had died already due to complications from hunger.

"We don't know, because these children dying of diarrhea, these women dying from preventable diseases, these elderly dying too early, die because they have been weakened by malnutrition, they have been weakened by lack of water, lack of sanitation and preventable disease kills them at intolerable levels," Egeland said.

Nomadic communities that depend on livestock for their survival have seen more than 80 percent of their animals die because of lack of water or fodder. Sporadic rains have been reported in the region, but experts said it was unlikely to be enough to reverse the drought and comes too late for most nomadic families.

Egeland said the U.N. appeal was for a comprehensive approach that would not only supply immediate emergency aid, but also take preventative and long-term steps to mitigate future droughts.

"It would be very, very immoral to save people this year and know that they could die again next year, or the year after," he said.

U.N. experts also have reported that the drought cycles have shortened, causing these kinds of problems more frequently, Egeland said. He added that long-term solutions must be found to help the nomads survive under the new climate conditions.

Egeland also emphasized a regional approach for the drought, centered where Somalia, Kenya and Ethiopia all meet. Somalia has been an especially difficult area to provide aid since pirates began intercepting ships carrying U.N. food to the country last year and there is still no effective central government in the country.

In Washington, President Bush said Thursday that the United States would send $92 million in aid to prevent widespread famine in the Horn of Africa, in addition to more than $150 million in emergency humanitarian food and other assistance the United States already has provided to the region since October 2005.