The U.N. is also effectively frozen out of sections controlled by leader Muammar Gaddafi's forces and is only seeking humanitarian aid for opposition-controlled areas.
"This appeal is based on a planning scenario projecting up to 400,000 people leaving Libya – including the 200,000 who have left to date – and another 600,000 people inside Libya expected to need humanitarian aid," said Valerie Amos, the U.N.'s humanitarian and emergency coordination chief.
The money is for camp management, food security, nutrition, health care, water, sanitation and hygiene.
Since Feb. 20, about 213,000 foreign workers have fled to Libya's borders with Tunisia, Egypt, Niger and now Algeria – an estimated 15 percent of Libya's foreign population – and hundreds of thousands more are expected to follow over the next three months, according to Amos and international migration officials.
Antonio Guterres, the U.N, high commissioner for refugees, says about 120,000 people have crossed the border into Tunisia from Libya since the crisis began. Most of the rest have gone over into Egypt, while a few thousand others fled into Niger and Algeria.
As part of the emergency appeal by 17 U.N. and other aid organizations, the International Organization for Migration said Monday it is seeking at least $49.2 million to provide food, water, shelter and medical care for up to 65,000 migrant workers caught up in the crisis.