School trust leaders have warned prime minister Liz Truss that they have “very grave concerns” about the financial viability of schools after ministers indicated that government-wide spending cuts could be made.

A letter signed by more than 350 academy trust leaders from the Confederation of School Trusts (CST) has been sent to both the prime minister and education secretary Kit Malthouse to call for more funding and to warn about the impact of any cuts. 

It comes after chief secretary to the Treasury Chris Philp said that government departments would stick rigidly to spending limits put in place last October and would be expected to find efficiencies.

• Warning: Further spending cuts will be looming disaster for schools
• Related: School budgets ‘worthless’ as costs soar
• Teacher pay: Threat of heads’ industrial action over ‘inadequate’ pay award

The letter from CST chief executive Leora Cruddas warns that this has further undermined trust leaders’ confidence in being able to balance academy trust budgets.

It adds: “We write to you to seek clarification on the position and to state again our very grave concerns about the viability and sustainability of schools and trusts if there is no further investment in school funding within this term of Parliament.”

The letter warns that energy cost pressures facing the sector come on top of “unaffordable public-sector pay awards and wider inflationary pressures”.

And it also warns that the government announcement on teachers’ pay rises was made after trust budgets had already been set.

The CST letter adds: “Our members have told us that these cost pressures are unaffordable within existing budgets.”

Tes reported last week that school sector leaders were warning that plans to make government departments stick to spending limits and undergo a “prioritisation exercise” to find savings would result in a “looming catastrophe” for schools.

Confederation of School Trusts’ letter to Liz Truss in full