"Days and nights have gone by, and still no assurance has been given for taking care of people who are sent out into the streets every day, as a result of lacking capacity to house them," the groups said in a statement.

They said that more than 1,000 asylum seekers have nowhere to go and survive in the streets, with winter rapidly approaching, and that their camp was hardly the solution.

They called on the government to make vacant buildings available as shelter.

The tents have been set up in the way that one of the non-governmental organisations -- Medecins Sans Frontieres (MSF, Doctors Without Borders) -- typically does in conflict zones.

There are around a dozen "family" tents capable of sheltering 50 people, three tents for health care, legal and social advice, and food support.

By mid-afternoon around 100 people were trying to enter the camp, set up by MSF, Medecins du Monde, Caritas International, CIRE and Vluchtelingenwerk Vlaanderen.

Belgium, like all European Union nations, is obliged to find housing for asylum seekers while their applications are processed. Between 17,000 and 19,000 would-be immigrants have been given shelter.