Labour and Conservatives have locked horns over education spending as General Election campaigning intensified with both sides insisting that their election promises were more generous to schools than their opponent's.

Ed Miliband promised to increase overall spending on education in England at least in line with inflation for the next five years if Labour won the May 7 poll and accused David Cameron of abandoning the UK Government's commitment to protect schools from austerity.

In response, the Tories claimed the Labour leader had failed to take into account the expected surge in numbers of pupils and insisted Mr Cameron's promise to protect funding per head in cash terms would leave schools almost £600m better off over the course of the next five years.

Mr Miliband returned to his old comprehensive school in north London to announce his pledge to at least maintain the Department for Education's £58bn budget in real terms each year of the next Parliament and said that his Conservative opponent's failure to commit himself to protecting non-school areas of DfE spending meant "big cuts" for early-years provision and further education if Tories gained power in May.

He drew a direct link between education spending and the current row over tax avoidance, arguing that if wealthy individuals and companies got out of paying their full share, it would mean less money for public services like schools.

Mr Miliband accused Tories of planning to sacrifice education to the demands of a "dangerous and extreme" policy of reducing public spending as a proportion of GDP to levels not seen since the 1930s.

"The next Labour Government will protect the overall education budget. Rising budgets, protected in real terms, every year; not cut as they will be under the Conservatives," he declared.

"Because our future prosperity depends on our young people and we will not, we must not, let them down," added the Labour leader.

But Nick Gibb, the Education Minister, pointed out that rising school rolls meant that Mr Cameron's promise would see the schools budget increase from £39,519m in 2015/16 to £42.297m in 2019/20. The Tories would spend a total of £590m more, he added.