Scores of upset parents packed into a St Margarets pub to discuss a new school funding formula which will throw already cash-strapped London schools into a “financial crisis”.

More than 9,000 schools in England are set to lose even more money as a result of a revised national funding formula (NFF), as cash will be re-allocated from urban areas to schools in rural and coastal areas.

London Councils, a bipartisan group representing all 32 boroughs, has said it will mean a cut to the budget of 70 per cent of the capital’s schools.

It comes at the same time they are hit with rising inflationary pressure, higher National Insurance contributions and a levy to pay for apprenticeships, from which schools traditionally do not benefit.

On Monday, March 13 parents from Orleans Park School and Orleans, St Stephen’s and St Mary’s primary schools – each in East Twickenham – flocked to the Turk’s Head pub in St Margarets to hear headteachers, school governors and political leaders discuss the NFF.

Elaine Ball, headteacher of Orleans Park School, told the funding shortfall would mean her school would have to increase class sizes and cut back on the number of GCSEs it would teach – which would lead to “very low morale”.

She said: “There have been massive funding reductions and a fantastic increase in costs recently; 75 to 80 per cent of expenditure is on teachers, so there’s very little wiggle room with our budgets.

“We have already reduced support staff and increased class sizes, which means increased teacher workloads.

“We won’t be making redundancies but we won’t be replacing teachers. We will get through this year but what the future holds I am not sure.”

Orleans Park School stands to lose £630,000 in real terms by 2019, according to the St Margarets Fair Funding for All Schools group – the equivalent of 15 teachers.

St Stephen’s, St Mary’s and Orleans Primary will lose £107,000, £140,000 and £145,000, respectively, the group says.

Twickenham MP Tania Mathias rushed to St Margarets from a late vote in the House of Commons, arriving as meeting chair Sandra Laville read out an apology for her absence.

Dr Mathias pledged to lobby Government ministers and apply pressure in the chamber to secure a more even arrangement for London schools.

She also invited residents to contact her on the issue, as did the borough’s Liberal Democrat leader, Councillor Gareth Roberts and ex-Twickenham MP Vince Cable.

Will Flower, who will soon have two children at St Stephen’s, said: “It’s great to see so many parents here, getting organised.

“We should all tell our children about what’s happening. We should get them politically engaged, too.

John Gibbs, who has one child at Orleans Primary and another at Orleans Park, said he was encouraged by the parents’ spirit of collective action.

Mr Gibbs urged parents from other areas of the borough to expand the campaign beyond St Margarets.