Thousands of children living in poverty across Flintshire and Wrexham

The End Child Poverty coalition, which commissioned the report showing almost a third of children across the UK live below the breadline, said families were already on a "cliff edge" before the coronavirus pandemic.

The research combined recent figures from the Department for Work and Pensions with local housing costs to produce new estimates for low-income families – those earning less than 60 per cent of the median income.

The analysis shows 6,813 children living in low-income families in Flintshire in 2018-19. Further to this, the report identified a total of 7,117 Wrexham children in the same situation during 2018-19.

The report is based on DWP data from March - and estimates of the effect of housing costs on poverty rates by Loughborough University's Centre for Research in Social Policy.

The figures show at least one in five children in every Welsh local authority is growing up in poverty, with last year's highest rate in Pembrokeshire (31.3 per cent).

In Flintshire, the number of children in low-income families fell from 7,514 in 2014-15, to 6,813 last year. For Wrexham, that figure fell from 7,417 to 7,117 during the same time period.

The coalition is calling on the UK Government to recognise the scale of the problem and its impact on children’s lives.

Ellie Harwood, Wales development manager for Child Poverty Action Group, said Wales has succeeded in reducing child poverty over the last three years, but rates remain "unacceptably high".

She added: “Whichever way you look at these figures, they show that child poverty exists in every corner of Wales, from the valleys to the coast, in our rural heartlands and our inner cities.

"With the pandemic threatening to push many more families into hardship, we need the Welsh Government to commit to a new child poverty strategy that sets out ambitious and measurable targets for eliminating child poverty altogether.”

A Welsh Government spokesperson said: “We have made significant resources available to help children and families most in need and we have seen some modest falls in child poverty in the face of a decade of austerity – this would suggest that, for many children in Wales, our policies are having a positive impact.

“But despite the progress we have made, we know there is much more to do and the pandemic will cast a long shadow on those who are most in need.

“We will continue to mitigate the impact of the pandemic for families living in poverty in light of the impacts of COVID-19."

They added that free prescriptions, free school meals, the education maintenance allowance and a generous childcare offer, meant some Welsh families were more than £2,000 a year better off before the pandemic.

Across the UK, the proportion of children in low-income families rose from 28 per cent to 30 per cent between 2014-15 and 2018-19.

Anna Feuchtwang, chair of ECP, said: "The children affected are on a cliff edge, and the pandemic will only sweep them further into danger."

ECP are calling on the UK Government to uprate housing assistance in line with inflation, abandon the "unconscionable" planned cuts to Universal Credit, end the benefit cap and the two-child limit on benefits, and increase child benefit.

A DWP spokesperson said they have already taken steps to level up opportunity across the UK by raising the living wage, ending the benefit freeze and injecting more than £9.3 billion into the welfare system.