The “deeply harmful” benefit cap must be scrapped, a children’s charity has urged a decade after the measure was brought in.

Some of the worst-affected families have less than £50 to live on each week after paying their rent, the Child Poverty Action Group (CPAG) said in its analysis.

The cap was introduced on April 15 2013, under the then-Conservative and Liberal Democrat coalition government which hailed it as a way of “restoring fairness to the welfare state”.

There is no rhyme or reason to the benefit cap and it is deeply harmful to children. All political leaders must commit to scrapping it before it pulls more children into its net

It sees the amount of benefits a household receives reduced to ensure claimants do not receive more than the cap limit.

Sir Iain Duncan Smith, who was work and pensions secretary at the time, said the cap was a key part to ending the days of “blank cheque benefits”.

But in its report, the CPAG brands Saturday an “unhappy anniversary”, saying “children and families are being pushed into deep poverty”.

The charity stated: “The Government claims that the benefit cap is needed as a work incentive.

“However, the Government’s own evaluation of the policy found that the vast majority of capped households do not move into work.”

A Government-commissioned evaluation, published in April, found that while the introduction of the cap saw some people move into paid work, move home or onto a benefit that exempted them, the vast majority, about 90%, of those affected did not and therefore just experienced a reduction in income.

The introduction of the cap saw claimants spending less on their children and essentials such as heating and food, the report from the Institute for Fiscal Studies (IFS) said.

The CPAG said its analysis suggested that in some areas of London, despite the cap being higher, a lone parent with three children has to cover all non-housing costs on £44 per week.

The group said that while “nowhere fares as badly as London, it is clear that capped families all across the country can be left with very little after paying their housing costs”, with its research showing a lone parent with three children was left with £106 after housing costs in Guildford, £147 in Brighton and Hove, and £170 in Oxford.

The CPAG described the Government’s rationale for the benefit cap as “flawed” and called on the Government to remove it, insisting this would “substantially reduce the depth of poverty for the 250,000 children currently living in households affected by the cap without harming work incentives”.

It added: “Removing the cap would only cost £300 million, 0.1% of the total amount spent on social security.”

Alison Garnham, CPAG chief executive, said: “The Government is at its most illogical with its benefit cap, the Department of Work and Pensions assesses families’ needs, determines their entitlement, then slaps a flat-rate cap on that entitlement, denying families what the department itself says they need.

“So needs don’t get met, entitlements aren’t paid and 250,000 children are trapped by the cap in deep poverty.

“No family should have to live on £44 a week.

“There is no rhyme or reason to the benefit cap and it is deeply harmful to children.

“All political leaders must commit to scrapping it before it pulls more children into its net.”

The latest Government figures, published in June, showed that some 97,000 households across much of the UK that had their benefits capped included children.

The total number of capped households increased by 3% in the latest quarter, according to the Department for Work and Pensions (DWP) statistics.

This means there were 2,900 more households subject to the benefit cap across England, Scotland and Wales as of February 2023 compared with November 2022.

Around 114,000 households had their benefits capped as of February 2023 and 86% of these included children.

Some 70% of households that had their benefits capped are single-parent families, the DWP said.

A Government spokesperson said: “We are committed to protecting the most vulnerable which is why we’ve increased the benefits cap in line with inflation and are providing record financial support worth around £3,300 per household.

“Our actions have helped nearly two million people, including 400,000 children, out of absolute poverty after housing costs since 2010, while the benefit cap provides both a strong work incentive and a vital safety net for those who need it.”