Prime Minister Tony Abbott says the government has secured national funding agreement on schools funding.

The federal government has secured an in-principle agreement for a national schools funding system, Prime Minister Tony Abbott says.

The agreement includes the $1.2 billion set aside by the former Labor government for the non-signatory states of Queensland, Northern Territory and Western Australia.

Mr Abbott said the agreement with the three was made by Education Minister Christopher Pyne in the past few days.

“Mr Pyne has … secured an in-principle agreement to a system which is fair and national,” he told reporters in Canberra on Monday.

“Given that we now have a fair and national deal, the government will put the $1.2 billion that Labor took out back into schools funding over the next four years.

“There will be full funding certainty over the next four years.”

The return of the $1.2 billion will bring total additional school funding over the next four years to $2.8 billion.

The government will also honour funding promised to non-government representative bodies for four years including $55 million to Catholic Education Commissions and $110 million to the Association of Independent Schools.

Education Minister Christopher Pyne said the government would amend the Australian Education Act in 2014 to “dismantle the regulation and red tape that made the model virtually incapable of being implemented”.

“Every student in Australia will be treated exactly the same way regardless of what jurisdiction they’re in,” he said.

Labor had made deals with NSW, Victoria, South Australia, Tasmania and the ACT, as well as independent and Catholic schools, but Queensland, Western Australia and the Northern Territory held out.

Last week the Abbott government announced it planned only to honour one year of the funding agreements set up by Labor under the so-called Gonski scheme, and allocate a further $230 million in 2014 to the states that did not sign on.

The fresh announcement on Monday by the prime minister is a reworking of that position and follows widespread criticism of the government over the past few days.

Mr Abbott said the coalition never agreed to a six-year education funding deal and doubted any of the state governments believed they would receive any of the promised cash beyond four years.

“I think they all thought that that money was essentially pie in the sky,” he said.

His government would deliver “four-year funding certainty” and negotiate a new agreement beyond that at an appropriate time, he said.

Mr Abbott warned it would be “very poor form” if the states reduced their education spending because more federal cash was on its way.

But he didn’t want to micro-manage the states by trying “to run public schools out of Canberra”.

He said the mid-year economic and fiscal outlook in December would make it clear where the Commonwealth was finding the extra $1.2 billion.

“We have identified appropriate savings over and above the savings that we identified prior to the election,” Mr Abbott said.

Mr Pyne said the in-principle agreements with WA, Queensland and the Northern Territory meant no state school would be worse off under commonwealth schools funding arrangements.

The prime minister defended the chopping and changing on schools funding over the past week, which has seen Mr Pyne claim a $1.2 billion shortfall, then pledge $230 million for 2014, and now a further $1.2 billion.

Mr Abbott said the decision meant the government was “more than keeping our commitments”.

“We want to keep our commitments in spirit as well as in letter,” he said.

On Sunday, he said the coalition would keep the promises it made, not the promises people thought it had made.

“We have identified what we think are perfectly suitable savings that won’t involve particular difficulties for parents, teachers, students,” he said.

Mr Pyne said while the government would alter legislation to remove some regulation, the funding for signatory states would be distributed in the same way as previously planned.

But conditions placed on NSW, Tasmania, South Australia, Victoria and the ACT won’t apply to the other three states.

“There is no plan to alter the way that the model will be delivered in the signatory states into the future,” Mr Abbott said.

“That won’t apply to Western Australian, the Northern Territory and Queensland.

“We would expect the signatory states to keep the promises that they made but at the end of the day that is a matter for those sovereign jurisdictions.”

The government will review the funding system in 2015, in line with legislative requirements.