SYDNEY, June 19 - The Nationals MP, who backed Labor's original Gonski reforms, has now broken ranks with the Berejiklian government in calling on politicians in Canberra to vote in favour of the needs-based formula.

"It improves the model, it's not perfect but it improves it to make it fairer,"  Piccoli said.

"That's why the (federal) legislation needs to be passed."

Piccoli admits the amount of funding on the table under Gonski 2.0 "isn't enough" but says states and territories can continue fighting for more cash once the improved system is in place.

"It's not just about money, it's about how it gets distributed," the ex-minister said.

"Under the current plan, over-funded schools continue to be funded.

"We will continue fighting over the money but don't lose the fight for the legislation."

Current NSW Education Minister Rob Stokes insists the state government will continue to push for the final two years of the original Gonski deal which would deliver more money.

While he's "pleased" the commonwealth is moving towards a needs-based model he says the message from the NSW government remains consistent.

"It continues to be our expectation that that agreement that remains on foot is honoured by the commonwealth government," Stokes said in a statement.