The prime minister and education secretary have been warned they risk a “decline in educational standards” if schools are forced to make further cost savings, in a joint letter from 12 organisations including school staff unions and parents’ groups.

In an open letter sent today to Liz Truss and Kit Malthouse, organisations including all four major teaching and school leaders’ unions, a membership body for parent-teacher associations, and the leading association for school governors have said they are “alarmed” at reports that the government may also be considering further “efficiencies” in public spending.

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They warn that school and college spending “has been cut to the bone” over the past decade, and that a real-terms cut in funding will be “catastrophic” because the amount of money already allocated to education “is not enough” to cover rising costs.

School funding: teacher jobs under threat

“If schools and colleges have to make further savings, this will inevitably mean reductions in teaching and support staff. This will result in larger class sizes, cuts to the curriculum and student support services, and cuts in extracurricular provision, such as school trips and clubs,” they write.

“There is a very real risk of a decline in educational standards. A failure to properly fund schools and colleges is short-sighted, short-term and short changes our pupils and students.”

Schools face mounting financial pressures this winter, including rising energy and catering costs, and having to fund teacher and support staff pay rises out of existing budgets.

Education sector experts and organisations representing school leaders, teachers and other staff have been sounding the alarm on these financial pressures for months now, describing them as a “perfect storm”.

While an energy support plan introduced from next month will provide some help, at least temporarily, there has been general disappointment at the government’s response, including a suggestion that schools could use “hard-earned” reserves to meet “cost challenges”.

Schools have warned of looming staff cuts since early in the year, and many of these have started to be realised.

The letter to the prime minister came after a similar one was sent by hundreds of school trust leaders earlier this week.

Mr Malthouse’s first major address as education secretary, at the Conservative Party Conference this week, did not mention school funding and instead focused on the government being “assertive” on school standards.

A DfE spokesperson said: “We understand that schools - much like wider society - are facing cost pressures due to international events driving up inflation and global energy prices. All schools will benefit from the Energy Relief Scheme, capping how much schools need to spend on their energy and giving them greater certainty over their budgets during the winter months.

“We are supporting schools with £53.8 billion this year in core funding, including an increase of £4bn this year compared to 2021-22. All schools can access a range of tools through our School Resource Management programme to help them get the best value from their resources, including recommended deals for energy costs and services related to energy.”

Today’s letter in full: