Almost half of the children at Saint Mary's primary school in London are entitled to a free school lunch owing to the fact they are from England's poorest families.

While charities argue that more pupils should be allowed access to taxpayer-funded meals amid a cost-of-living crisis caused by sky-high inflation, the government of Prime Minister Rishi Sunak is resisting such calls.

At 48%, the proportion of St Mary's children entitled to a free school lunch is far higher than the national average.

"It's shocking to think that a number of children and our families are struggling to make ends meet and struggling to provide the food they need for their families," Claire Mitchell, part of the school's leadership team, told Agence France-Presse (AFP).

Other families who ought to benefit from free school meals cannot because they earn above the cut-off point, which stands at £7,400 ($9,163) per year in England.

"The threshold is just set too low, and is out of step with other devolved nations in the UK," according to Stephanie Slater, founder and chief executive of charity School Food Matters.

"In Northern Ireland, the threshold is £14,000 pounds. In Scotland and Wales they are just beginning to roll out universal free school meals, meaning that every child in every school will eventually get a free meal at lunchtime."

By comparison, just over one-third of pupils in England benefit from assistance worth about 2.40 pounds ($2.93) a day.

According to the Child Poverty Action Group, one in three children in England, which it says live in poverty, do not qualify.

'Started with pandemic'

At Saint Mary's, a Roman Catholic school, many parents are struggling to cope with raising energy and food bills.

The school has its own food bank offering donated staple items like bread and milk for free.

"The pandemic is for us where we really started noticing the change when families were either losing jobs or unable to work as many hours as before," said Mitchell.

According to the Sutton Trust, the number of families unable to afford school meals in England has jumped by 50% during the inflation surge.

The charity has meanwhile hit out at the government for not widening access in a recent budget.

England and Manchester United footballer Marcus Rashford, who benefitted from free school lunches, has led a campaign for greater availability.

He has been joined by the likes of singer Zayn Malik, London Mayor Sadiq Khan and Ken Murphy, chief executive of British supermarket giant Tesco.

"When we talk about hunger, we're talking about children coming to school and relying on a hot, nutritious meal at lunchtime," said Slater.

"For those not entitled to a free lunch but find themselves in difficulty, schools will either subsidise free meals for those children out of their own school budgets, or families pack lunch boxes that are inadequate as they struggle to find good nutrition," she told the AFP.

For Mitchell, a hungry child "will struggle to focus and concentrate. If they're not reaching their full potential now, it'll be harder to catch up," she remarked.