Justine Greening has repeatedly refused to say whether Conservative school funding plans would represent a real-terms increase in per pupil funding.

Appearing on BBC Radio 4’s World at One this afternoon, the education secretary said her party’s manifesto pledge of £4 billion extra funding a year by 2022 would represent a real-terms increase in overall funding.

However, when pressed on whether this would be a real-terms increase per pupil, she dodged the question.

Ms Greening said: “The prime minister was clear that, actually, no party is going to be able to guarantee that. But, in the end, we have sustainable funding for schools in place, a real-terms increase in every year of the coming parliament, record funding continued, pupil premium in addition to that, and continued improvements in standards.”

The Institute for Fiscal Studies has calculated that the Tory pledge would equate to a real-terms cut in spending per pupil of 2.8 per cent between 2017-18 and 2021-22.

‘Improved nutrition and healthier investment’

Shadow education secretary Angela Rayner said Labour “absolutely guaranteed” there would be a real terms increase in per pupil funding in schools.

Ms Greening also defended the Conservatives’ costings for their plan to give free breakfasts to all primary school children, instead of free lunches for all infants.

Asked if the Tories had got their initial figures wrong, Ms Greening said: “No, we said that was the additional money coming into the department in order to be able to deliver that policy.

“There was already money there to deliver improved nutrition and healthier investment per pupil.”

‘Huge mistake’

She backed an analysis from Education Datalab which suggested that if the take-up of breakfasts was just 20 per cent and breakfasts were delivered before the school day, rather than in lesson time, the cost would be £174 million a year.

Ms Greening said: “Overall, Datalab have talked about a cost of around £174 million or so. Our own calculations backed that up.”

Russell Hobby, general secretary of school leaders’ union NAHT, said schools had invested heavily in new kitchens and equipment to deliver the free school lunches policy when it was introduced in 2014.

He added: “It would be a huge mistake to end universal infant free school meals without any proper evaluation of the project. Hundreds of millions of pounds of investment is set to be wasted, with no clear rationale apart from a desire to save money.”

Want to keep up with the latest education news and opinion? Follow Tes on Twitter and like Tes on Facebook.

For all the latest news, views and analysis in the run up to voting day, visit our general election 2017 hub.