At least 500,000 people are living outdoors in improvised camps outside the Haitian capital, Port-au-Prince, following last week's huge earthquake in the Caribbean nation.
The International Organisation for Migration has identified nearly 450 settlements, of which about 100 are still to be assessed by officials or humanitarian agencies.
Most have been cobbled together with blankets, cardboard or bits of debris, AFP reports, while some have received tents from international aid organisations or United States forces.
Efforts continue to get aid to the hundreds of thousands in the capital and other parts of the country, but, the BBC reports, many who live in the vast encampments have seen no relief at all.
The American military is operating at four airports in the area as it tries to coordinate aid distribution, and officials say they are giving the highest priority to shipments of water.
It's feared as many as 200,000 people died, and an estimated 1.5 million people were left homeless when the 7.0 earthquake struck on 12 January.
The government of Haiti says the bodies of at least 75,000 people have been buried in mass graves. Many more are trapped in the rubble and some have remained lying in the street.
Plan to resettle many in makeshift camps
Haitian officials say they will resettle up to 400,000 people from Port-au-Prince. Interior Minister Paul Antoine Bien-Aime says buses will take people from makeshift camps to villages in the north and south.
Meanwhile, the home-building charity Habitat for Humanity hopes to erect thousands of expandable one-room houses in Haiti.
New Zealand has doubled its contribution relief and recovery efforts to $2 million.
In New York, United Nations Secretary-General Ban-Ki Moon has met former American president Bill Clinton to enlist his support for a disaster relief programme that will give 200,000 Haitians jobs clearing debris from the streets.