The Archbishop of Wales threw the church's weight behind the anti-bedroom tax campaign yesterday before a new wave of demonstrations.

Around 37,000 households in Wales are affected by the "over-occupancy charge" - but there are just 400 vacant one-bedroom social housing properties available to rent.

Rev Barry Morgan told the Con-Dem government that its policy "penalises the most vulnerable" and has "no place in Wales today.

"The mark of a civilised society is how well it looks after its poorest and most vulnerable people," he added.

"This tax is depriving those in need of the means to live at the most basic level, of the means to bring up their children, and is creating insecurity and debt."

The archbishop signed a joint statement against the tax with union PCS leader Mark Serwotka, Welsh Assembly members, author Owen Jones and housing experts.

It says Welsh tenants are suffering because the coalition chose to introduce a "bedroom tax on the poor instead of a mansion tax on the rich."

But it insists that Welsh councils can follow the lead of their Scottish counterparts and refuse to evict tenants with arrears from the tax.

Their call sets the scene for a protest march through Cardiff on Saturday afternoon, which is part of a Britain-wide day of action.

Speakers at the demonstration, which starts at 1pm from City Hall, includes Deputy Minister for Tackling Poverty Vaughan Gething, trade union leaders and affected tenants.