By Jonah Fisher
BBC News, southern Sudan
The UN's top humanitarian official says the world is committing a historic mistake by failing to support the peace deal in southern Sudan.
Average life expectancy in southern Sudan is just 42 years
In January, the main rebel group signed an agreement with the northern government, bringing to an end to 21 years of civil war.
On a visit to the south, Jan Egeland said the needs were overwhelming.
He said just 5% of the required funds required have so far been given.
Southern Sudan is one of the poorest places on earth.
Life expectancy is just 42 years and only a quarter of the population can read.
Any infrastructure that did exist was destroyed by the long civil war between the black African south and the Arab north.
With the ending of that war in January, hopes were high that the south would begin to put the conflict behind them, and roads, hospitals and schools would all be built.
Sudan asked for over $500m from the international community but so far they have given just $24m.
"I fear the world is making a historic mistake here in southern Sudan," Mr Egeland said during his trip to the region.
"Now we have a peace agreement. Now we have three, four months of cementing that peace agreement.
"We are not getting the money, neither for the refugees returning to southern Sudan or to the impoverished war stricken population in this area," he added.
"The world has to respond. It is unbelievable that they are waiting."
Other humanitarian appeals have diverted money away.
The Asian tsunami and the Darfur crisis have both been much more successful at raising funds.
A donor conference for the south is due to be held in Norway next month.
Having pushed hard for the civil war to end, the people of southern Sudan will hope the international community has not forgotten them in times of peace.