The number of Birmingham social housing tenants in rent arrears has almost doubled following the introduction of bedroom tax.

Around 14,000 saw their housing benefit cut in April at a time when 2,816 were already behind with their rent.

That has soared to 5,390 in just three months – a 91 per cent rise.

The benefit cut came down on those who have spare bedrooms and is designed to encourage families to down-size, freeing up larger homes.

Birmingham’s Labour cabinet member, Coun John Cotton, said: “Sadly, the dire warnings about the impact of this reform are now coming to pass and, as expected, many of the most vulnerable people in Birmingham are struggling to pay the new charges. Once again the local authority is left to pick up the pieces.

"We are doing everything we can to provide a safety net, but the number of affected people in arrears has almost doubled in just three months. I can only see that situation getting worse.

“As we have consistently stressed, there is a shortage of one-bedroom properties in Birmingham and across the country, so people are now left in properties they can no longer afford.”

He said that each statistic represents a household in crisis.

Coun Cotton added: “We’re talking about families and individuals across Birmingham being driven to despair by a cruel charge that isn’t even doing what it set out to do.”

Households that have a spare room have seen an average £14 a week reduction in housing benefit.

Solihull grandmother Stephanie Bottrill, who walked into the path of a lorry on the M6, has become a focus for the anti-bedroom tax lobby. The mum-of-two and grandmother was told she would have to find £80 a month in rent because she lived alone in a three-bedroom house.

She left a note making it clear she could not go on after being forced from her home of 18 years by the ‘bedroom tax’.

The council has set up a £2 million discretionary payments fund to help those in difficulty. But it is feared demand could be too great as 2,000 people applied for help during the first two weeks of April alone.