Education secretary Gavin Williamson has faced pressure from Conservative MPs to guarantee extra money for schools in the areas they serve.
Mr Williamson insisted that more was being invested in schools and high-needs education over the next three years, including an additional £2.6 billion in 2020-21.
But Tory MPs were among those to raise concerns over long-term underfunding in their constituencies.
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Gareth Bacon MP said that the total schools block grant in Orpington had gone down since 2013, while funding across London regionally had increased by 4.5 per cent.
He added: “I know [Mr Williamson] recognises historic imbalances towards metropolitan areas, so what reassurances can he give me and the excellent schools in Orpington that the NFF [national funding formula] rebalances funding?”
Mr Williamson said his department and the government were “working towards having a hard national funding formula” to make sure there was “a fairness in funding” across the country in every constituency.
Of the issues raised by Mr Bacon, he said: “It’s certainly something we’ll listen very closely to.”
Giles Watling, Conservative MP for Clacton, said: “The national funding formula is letting down some of Clacton’s schools financially because of the way Essex County Council is rolling it out.
“Can the department not have oversight and work with Essex County Council to rebalance the books in favour of our hard-pressed schools in Clacton?”
Mr Williamson said he hoped the council would move towards the NFF “as rapidly as possible” and use it to inform how much funding it provided per pupil at each school.
Selaine Saxby MP also noted: “Schools in my North Devon constituency face the dual challenge of rural and coastal deprivation.
“And despite the very welcome increase in funding, Devon will remain in the bottom 10 per cent of local authorities in terms of dedicated schools grant per pupil.
“Will the minister work with me to ensure North Devon schools have the funding they need to support and encourage the aspirations of every child?”
Mr Williamson, in his reply, said: “I’m sure she will be welcoming the 6.5 per cent increase per-pupil increase in North Devon.
“This is making a real difference and will make a real difference to the attainment of children.
“This is a government that is delivering extra money for schools right across the country.”
He added that raising standards in every school was also the government’s aim.
Michael Fabricant, MP for Lichfield, said that Staffordshire had been “right at the bottom of the pool as far as getting money is concerned” compared with other counties.
He asked Mr Williamson to offer good news to schools in both their constituencies, considering that the education secretary represents South Staffordshire.
Mr Williamson said schools were “enjoying an 8.2 per cent cash increase, as well as an over-5 per cent increase in the constituency of Lichfield”.
