Seven in every 10 households hit by the benefit cap in Cornwall are single-parent families, new figures reveal.

The Conservative Party says the flagship welfare reform is designed to ensure that work pays, but charities argue the "cruel and ineffectual" policy pushes vulnerable families into poverty.

The latest Department for Work and Pensions figures show 420 Cornwall households had their benefits capped during August.

Of these, 295 (70 per cent) were single-parent households.

Single-parent charity Gingerbread says it is "deeply concerned" by the impact the policy is having on such families, with parents of young children often struggling to move into work.

The benefit cap limits the total amount of income a household can receive from certain benefits, and is implemented by reducing either their housing benefit or Universal Credit payments.

Currently, the cap kicks in at £20,000 per year for families outside of London, and £23,000 for those in the capital.

Child tax credits and child benefit both count towards the income threshold.

David Samson, welfare benefits specialist at charity Turn2us, said: “The benefits cap is a fundamentally flawed policy which breaks the link between need and entitlement.

"It works by taking away money that the welfare system has calculated a family needs. As a consequence, it is pushing many into poverty.

"As a society we believe that your background shouldn’t limit your opportunities. But if you are a child of a single parent affected by this policy, you’re less likely to be able to take part in a sports club or even have a healthy meal."

Across Great Britain, more than 79,000 households had their benefits capped in August, 71 per cent of them single-parent families.

On average, single-parent households had their benefits capped by at least £50.

The figures also reveal the number of children in each of the households that had their housing benefit reduced, including couples with children.

In Cornwall, three-child families were most commonly affected, accounting for 47 per cent.

The information is not published for those who had their Universal Credit reduced.

Laura Dewar, policy officer at Gingerbread, said: "The benefit cap has a disproportionate impact on single parents including those with babies and toddlers.

"It has meant many single parents simply do not have money for essentials like rent – putting them at risk of homelessness.

"We want to see this cruel and ineffectual policy overturned."

Employment minister Mims Davies said: “The benefit cap was introduced so it always pays to be in work. It is fair to the taxpayer while ensuring a large safety net for the most vulnerable.

“It is part of a package of policies that has seen the number of single parents in work reach a record high and the number of children living in a workless household reach a record low."