Image copyright Getty Images Image caption School budget shortfalls are "unsustainable", heads have told MPs

Head teachers in England are calling on MPs for answers on school funding shortages - saying that they are still no closer to knowing their budgets.

About 4,000 heads across 17 councils, mostly in southern England, are writing to their MPs warning that schools face job losses and cuts to subjects.

They say that the current level of school funding is "unsustainable".

The Department for Education says that it is committed to increasing levels of school funding.

But there is uncertainty over the Conservatives' manifesto promise for an extra £1bn per year, as that depended on funding from scrapping universal infant free meals - a proposal which is no longer confirmed.

Ministers say they are "reflecting" on plans for school meals and "will come forward with proposals in due course".

Parent funding

The education department has so far not presented a revised plan for school funding - and head teachers are calling for urgent "clarity" on resolving budget shortfalls.

The head teachers, writing a joint letter to MPs, say they are concerned about "being placed in the unwanted position of having to ask parents for regular financial contributions in order to prop up our devastated budgets".

The heads are in 17 authorities with many Conservative MPs, in Brighton, Cambridgeshire, Cornwall, Devon, Dorset, East Sussex, Essex, Hertfordshire, Norfolk, Northamptonshire, Oxfordshire, Peterborough, Suffolk, Surrey, Thurrock, West Sussex and Wokingham.

They say they have been asking for a decision on budgets for two years, but "unfortunately schools continue to wait in vain for improved funding".

Head teachers want to know whether extra money pledged in the manifesto is "still on the table" and details of minimum per pupil funding levels.

They are also calling for a clear timetable for the implementation of the new National Funding Formula, which is meant to tackle inconsistencies in the amounts received by individual schools.

Adding to the pressure on funding are calls for the lifting of the cap on public sector pay, which could see increases in teachers' salaries.

The pay review body for teachers' pay is expected to publish its recommendations in the summer.

If a bigger increase is proposed and accepted by the government, this would require a further increase in the budget for schools, with teachers' pay representing the biggest slice of school spending.

Jules White, the West Sussex head teacher who has co-ordinated the letter to MPs, says a pay increase for teachers would be welcome, but it needs to be fully funded.

"Our campaign is focused on adequate funding... to ensure that there are enough teachers, support staff and equipment in every school.

"It's no good just awarding a pay increase if this squeezes school budgets and overall resources still further," he said.

The Department for Education said that it was considering plans for a new funding formula for schools.

"The core schools budget has been protected in real terms since 2010 and is set to rise from £41bn in 2017-18 to over £42bn in 2019-20 with increasing pupil numbers," said a DFE spokeswoman.

"We have also consulted on a national funding formula for schools to make funding fairer. We received over 25,000 responses to the consultation, which we are analysing in detail and will respond to in due course."