A legal challenge over claims that the Government's so-called "bedroom tax" unlawfully discriminates against disabled people in social housing has been dismissed by the High Court.
But campaigners said they welcomed court criticism that the Government has been aware since May last year that the law must be changed to provide for disabled children but failed to act early to make the necessary regulations.
Lord Justice Laws, sitting with Mr Justice Cranston, said the current state of affairs "cannot be allowed to continue".
Lawyers acting for disabled people said the ruling meant that the Government must now act "very speedily" to show there should be "no reduction of housing benefit where an extra bedroom is required for children who are unable to share because of their disabilities".
The legal teams said they would fight on after losing the main aim of their challenge - to block the controversial housing benefit regulations that came into force on April 1.
The new regulations involve reductions in benefit payments to tenants assessed to be under-occupying their accommodation.
Under new ''size criteria'', tenants with one spare bedroom have had a payment reduction of 14% and those deemed to have two or more spare, a reduction of 25%.
Human rights lawyers say that, unless the families move from their homes into smaller properties, they face building up rent arrears and being forced out anyway.
Ten cases were brought before London's High Court to illustrate the serious impact of the regulations on disabled people up and down the country.