The United Nations says it has received only $22 million of the $415 million it says it needs for the emergency response to the 7.8-magnitude Nepal earthquake.
Jamie McGoldrick, the U.N.'s chief official in Nepal, said donations for the humanitarian efforts in the impoverished Himalayan nation following the earthquake need to be "dramatically ramped up."
McGoldrick said relief personnel are now working "so that people have roofs over their heads and their other urgent needs are addressed before the monsoon season starts."
Monsoon rains usually start in June, triggering avalanches and flooding.
More than 7,800 people were killed in the April 25 earthquake.
The U.N. estimates that as many as eight million people have been affected by the quake.
"We cannot run our responses on credit cards," said Paul Dillon, a project manager at the International Organization for Migration. "Those who have offered help need to make good on their pledges."