Melinda Pavey on Monday confirmed the coalition government had sought legal advice on its options for the agreement, with state and federal water ministers to meet next week to discuss potential changes.

Ms Pavey and NSW Deputy Premier John Barilaro have publicly demanded changes to the plan, saying drought-stricken NSW had no more water to give to South Australia or for environmental flows.

Mr Barilaro has repeatedly threatened to take NSW out of the water-sharing agreement.

The NSW government has set out demands including the retention of 450 gigalitres currently earmarked for river recovery efforts.

They also want NSW water resource plans - which set rules on how much water can be taken from the system - to be paused until the drought has broken, and for the barrages on SA's Lower Lakes to be lifted.

Ms Pavey said the Murray-Darling Basin Plan "was never meant to be static" and NSW did not want to be "forced into those other options (of walking away)".

But the state had been given legal advice it could do so.

"There is capacity for us to walk away but that's something we need to be able to consider in collaboration with other states," Ms Pavey told reporters.

"I'd prefer to get a better result for the nation and our state.

"Why shouldn't there be a complete and utter dashboard of where the water is going? It's not an unreasonable thing for anyone in the community to expect."

Ms Pavey also hit back at reports on Monday that NSW may not complete eight of its 20 water resource plans due by the end of the year, saying both SA and Victoria were similarly behind schedule on their plans.

National Conservation Council chief executive Chris Gambian said NSW's failure to complete the eight plans would be unacceptable and accused the Nationals of undermining the basin plan for the benefit of irrigators.

"The Nationals blame the drought, but the drought has nothing to do with it. The Nationals have dragged their feet in implementing the basin plan at the behest of their irrigator mates," Mr Gambian said in a statement on Monday.

The federal government last week ordered an investigation into the operation of the Murray-Darling Basin Plan - to be conducted by former federal police chief Mick Keelty - to report in March next year.

Australian Associated Press