Analysis from the respected Institute for Fiscal Studies (IFS) reveals Labour’s pledge of an extra £10.5 billion for schools over the next three years only amounts to £7.5 billion when inflation is taken into account.

However, it is still more than the Conservatives’ pledge of £7.1 billion, which amounts to £4.3 billion in real terms between next year and 2022-23.

And it is more than the Lib Dems’ pledge of £9.1 billion by 2022-23, which amounts to £5.6 billion in real terms.

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Describing his findings, IFS research fellow Luke Sibieta said: “I think it kind of reflects the overall pattern that Labour are putting in more money for public services. It tells you their priority is public services.”

He said both the Lib Dem and Conservative amounts were sufficient to reverse the real-terms cuts to school funding (of around 8 per cent) since 2009, with the Lib Dems offering slightly more.

However, he said the Labour plans provided a 15 per cent increase in spending per pupil between now and 2022, which was “an extremely significant rise” and that it  allowed for some “significant increases” in school spending, including a rise in teacher pay.

He said the 5 per cent teacher pay rise pledged in today’s Labour manifesto could cost more than £3 billion, but did not want to comment on how much a Conservative pay award for teachers could cost until further details were released.

Mr Sibieta said both the Conservatives and Labour had each double- and triple-counted in the funding figures they initially put out - with the Conservatives citing £14 billion and Labour citing £25 billion - and he said he was “staying clear of those amounts”.