Campaigners have attacked a "devastating" High Court ruling that the Coalition Government's bedroom tax is legal.

Opponents of the policy had hoped to stop it in its tracks by proving it unlawfully discriminates against disabled people in social housing.

That claim was thrown out yesterday although the court did find that ministers were not doing enough for disabled children.

Within hours of the ruling Coalition ministers announced they were doubling the funds available to those suffering through the benefit cut.

Lawyers representing claimants last night vowed to appeal against the decision.

The Scottish Government estimates that the so-called bedroom tax affects 52,000 homes in Scotland.

Since the policy was introduced in April many council tenants with a spare bedroom have seen a 14% reduction in their housing benefit. Scottish Welfare Minister Margaret Burgess, who met with welfare minister Lord Freud yesterday, said she was "disappointed" by the ruling.

She warned it was "wrong " the bedroom tax applied to those in council owned temporary accommodation, a figure higher in Scotland than in other parts of the UK.

Labour's shadow welfare minister Stephen Timms said the policy "combines incompetence with cruelty".

But the Deputy Prime Minister Nick Clegg defended the policy, saying it was necessary with two million families still on housing waiting lists across the UK.

Graeme Brown, director of Shelter Scotland, said: "This is devastating news for disabled adults and families with disabled or vulnerable children, who'll be put at real risk of homelessness for having a bedroom they can't do without."

The Department for Work and Pensions said it would double the funds for those affected by the bedroom tax to £65 million.