Labour leader Ed Miliband said the benefits cap should take into account housing costs in each region.
"We've said we're in favour of a benefit cap but it has got to be adjusted regionally depending on housing costs in each region," he said.
"The danger of the way the government is doing the cap is that it forces people into temporary accommodation, bed and breakfast accommodation, which drives up costs, not reduces them.
"And actually what we're seeing with the welfare bill is, despite the cuts the government is making, the welfare bill rising and not falling."
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