Education Minister Simon Birm­ingham has seized on fresh figures showing the gap in federal funding between similarly needy schools in the Northern Territory and Western Australia growing to more than $2000 per student by 2019.

As Labor and the eastern states argued that the Coalition’s push to kill off the Gonski needs-based schools funding model would leave schools much worse off, Senator Birmingham said ­without a shake-up the current arrangements would only continue to distort the federal funding that went to students with identical needs.

“These figures fly in the face of some of the political grandstanding we have seen recently,’’ Senator Birmingham told The Australian. “Far from Labor’s Gonski arrangement fixing itself into a nationally consistent model after year six, the distortion of need actually gets worse. Unless we fix it, the inequality of funding between students set out in Labor’s version of Gonski would only get worse.’’

Fresh modelling shows that by 2019 — the sixth year of the ­Gonski agreements — the disparity between some states worsens on a like-for-like comparison.

The federal analysis shows a hypothetical public school in NSW with the same level of dis­advantage would be provided with $3236 per student in federal funding in 2017, while a similar school in South Australia would get $2897 per student.

In the Northern Territory it would get $4224, leaving Western Australia trailing with $2649 per student — a gap of $1575. But by 2019, this gulf between the same schools in the Territory and the west grows to $2109 per student.

South Australia, however, ­almost catches up with the other states and overtakes Queensland with the commonwealth providing $4139 per student in 2019.

“Contrary to some suggestions, there is no magical resolu­tion in the fifth and sixth years of Labor’s 27 different school funding models,’’ Senator Birmingham said. “In fact, the disparity between what federal funding a disadvantaged student gets in one state compared to that same stud­ent in another state blows out to more than $2000 by 2019.”

The Coalition wants to negotiate a new nationally consistent funding model to begin in 2018 that erases the deals that favour some states. Senator Birmingham has reiterated the Coalition’s support for the principles of needs-based schools funding, including extra loadings for disadvantaged, indigenous and rural students, and those with disabilities.

But NSW Education Minister Adrian Piccoli said that if Senator Birmingham wanted to fix the anomalies in the way the Gonski agreements were implemented, he should talk to the review’s ­authors, including businessman David Gonski.

“They spent a year and a half intensively looking at schools funding across Australia and they came up with … recommendations,’’ Mr Piccoli said, adding it would be a return to the bad old days and the Gonski agreements’ anomalies could be fixed.