The Turnbull government denies it has picked a fight with Catholic schools as it refuses to budge on its school funding plans.

Catholic education authorities estimate fees at Sydney schools could rise by $5000 over the next five years, and $4000 in Melbourne, News Corp reported on Sunday.

But the government says its new plans for funding are fair and will lead to Catholic schools getting an extra $1.2 billion over the next four years.

Treasurer Scott Morrison said he would always argue for fairness.

“We can’t walk away from the principle which says that every child’s funding for their schooling should be based on a clear standard,” he told the Nine Network on Sunday.

“There shouldn’t be special deals, there should be one deal.”

Labor is siding with Catholic educators, saying it trusts what the school systems say over the government.

Shadow treasurer Chris Bowen said several times on Sunday the Catholic system would be in meltdown by the end of the decade under the government’s plan.

“Their one-size-fits-all model will have very significant ramifications for the 20 per cent of Australian students educated in the Catholic system,” he told ABC TV.

“The Catholic Education Office themselves have said there’s been an utter breakdown of trust between the Catholic education system and the government.”

He labelled the government’s so-called Gonski 2.0 plan a pale imitation of Labor’s policy, with the opposition wanting a much bigger increase in funding.

The government plans to boost its share of funding from $17.5 billion in 2017 to $30.6 billion by 2027, with the aim to bring all schools to the same level per student once state government cash is added.

Education Minister Simon Birmingham said the modelling showing large hikes in Catholic school fees was fundamentally flawed.

“I am committed to stopping the school funding wars and I urge all parties to end their scare tactics and stop their campaigns for special treatment,” he said.

The government’s funding formula takes into account the socio-economic status of a school community, with those where parents are less likely to be able to pay higher fees slated for more government money.

Mr Morrison said the government received a letter on Sunday from the Australian Association of Christian Schools – some of whose members will actually lose money under the plan – backing the funding arrangements because of their fairness.
-AAP