Up to one million foreign workers and others trapped in Libya are expected to need emergency aid because of fighting in the North African nation, aid officials said Monday as they sought $160 million to deal with the crisis.

"This is our assessment of what we might need over the next three months to look after those migrants who are leaving Libya across the borders with Egypt and Tunisia and Niger and we need to move them through very quickly and get them back to their countries of origin," Valerie Amos, the UN's humanitarian and emergency co-ordination chief, told CBC News in an interview Monday.

"We saw a huge number of Egyptians and Tunisians returning on the border where I was over the weekend and we had 14,000 Bangladeshis that we need to get back home and we're going to start that process tomorrow.

"We also have people from a huge number of sub-Saharan African countries — Nigeria, Ghana, Sudan, but also refugees from countries like Somalia — who will not be able to go back home and who we need to resettle somewhere, so some of the money is for that."

An evacuee bathes Monday at a UN refugee camp near the border crossing of Ras Jdir, Tunisia, after fleeing violence in Libya. (Yannis Behrakis/Reuters)

Specifically, the money is for camp co-ordination and management, food security, nutrition, health care, water, sanitation and hygiene.

The UN is effectively frozen out of sections controlled by leader Moammar Gadhafi's forces and is only seeking humanitarian aid for opposition-controlled areas.

The appeal is based on a projected 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.

At least 213,000 foreign workers have fled Libya's violence and hundreds of thousands more are expected to follow over the next three months, according to Amos and international migration officials.

UN Secretary-General Ban Ki-moon said he's deeply concerned about the plight of the many migrant workers and other civilians who are bearing the brunt of the fighting in Libya, particularly in the western portion that includes Gadhafi's stronghold in the capital, Tripoli.

Ban appointed former Jordanian foreign minister Abdelilah Al-Khatib as his special envoy to Libya and urged authorities to ensure the safety of all foreigners and provide unhindered access for humanitarian aid.

He also called for an immediate halt to what he called Gadhafi's "disproportionate use of force and indiscriminate attacks on civilian targets."