SA’s new water minister says he will fight a cut of 605 gigalitres of Murray Darling water meant for the environment.

Water minister David Spiers will meet with the federal minister and bureaucrats on Wednesday to talk about planned changes.

Ahead of the meeting, he told reporters he would push Canberra and the other basin states to stick to the plan's original 2012 water targets.

This would mean rejecting new expert reviews that recommend more water for irrigators.

It is the latest blow for the basin plan, which is on shaky ground after NSW and Victoria threatened to walk away.

The states were incensed after Labor and Greens senators voted last month – supported by former SA premier Jay Weatherill – to block a 70GL cut for environmental flows in the northern basin.

A disallowance motion for the 605GL cut in the southern basin's water recovery target has been tabled in Parliament and should be debated in May.