Housing organisations have expressed scepticism about Government plans to give State land in urban areas to private property developers in exchange for affordable housing in the suburbs.
The Taoiseach, Bertie Ahern, is due to announce the move at the biennial conference of the Irish Congress of Trade Unions in Belfast today.
The housing organisation Threshold said it welcomed any move to provide more affordable housing.
However, spokesperson Aideen Hayden said she believed the Government's new plans would simply help it meet previously announced targets that fell well short of what was needed.
Ms Hayden also said building more houses in the suburbs, particularly in Dublin, would hamper efforts to develop sustainable communities within urban centres.