The United Nations is appealing for almost half a billion dollars in urgent aid to provide humanitarian assistance for more than 8 million people in Iraq.

Lise Grande, the U.N. humanitarian coordinator for Iraq, said Thursday that "more than 50 percent of the operation will be shut down or cut back if money is not received immediately."

In an appeal in Brussels, the U.N. and its partners asked for $497 million to cover the costs of shelter, food, water and other aid over the next six months.

The conflict has forced some 3 million people from their homes and scattered them, hampering aid efforts.

The U.N. estimates that 10 million Iraqis could need aid by the end of the year.