Lib Dem Care Minister Norman Lamb has said the evidence was "clear" that the controversial "spare-room" policy was not working.
He told BBC2's Newsnight that in his North Norfolk constituency he came across "many cases" where people may be willing to move, but the state of the housing market and the shortage of social housing just makes it impossible.
"So they are stuck in a situation," he said.
"It was also wrong for disabled people who needed an extra room for a carer to use or to be adapted in some way to be hit".
The Liberal Democrats called for a reform of the bedroom tax in a dramatic withdrawal of support for the controversial welfare reform.
More top news
The 'Let Our Kids Be Kids' campaign wants parents to keep their children off school saying they are "over-tested and over-worked".
Nicky Morgan is expected to defend the proposal when she fields questions at the National Association of Head Teachers' annual conference.
Phone charges in the European Union will drop by about 75 per cent from today as part of an interim cap ahead of a full ban next year.