Humanitarian groups and Chadian authorities need urgent funding to support thousands of refugees fleeing across the border from neighboring Sudan, according to the World Food Programme.
The UN has said as many as 20,000 people have crossed from Sudan into Chad since fighting erupted between factions led by rival generals earlier this month.
"It’s extremely urgent because in six to eight weeks we will never be able to reach those places because of the rains," said Pierre Honnorat, the WFP's country director for Chad.
Food and aid packages were distributed to refugees arriving at the border at Adre this week.
Two weeks of fighting have turned the capital Khartoum into a war zone and thrown Sudan into turmoil.
A wide-ranging group of international mediators — including African and Arab nations, the UN and the United States — were intensifying their pressure on the rival generals to enter talks on resolving the crisis.