More than 70 elected leaders of the state's peak farming body have called on the Murray-Darling Basin Authority to ditch its draft plan aimed at rescuing the rivers and to recalculate the irrigation water cuts it says are needed in every valley.

''This is not a case of negotiation,'' said the president of the NSW Farmers' Association, Charles Armstrong, after the unanimous vote at a Sydney meeting of representatives from across the state.

The authority had done nothing to justify the 37 per cent average water cuts to agriculture across the state and its draft plan was ''a huge black cloud'' hanging over farmers and their communities, he said.

''The ability of people to invest, the ability of banks to continue to back farmers and other businesses in regional areas is really under question.

''We will see a huge restructure of this area ... Maybe it will mean a vacant NSW and [a state which becomes] a huge national park, where a whole lot of people go hungry.

Farmers call for Murray Darling river plan to be ditched

meanwhile .....

The NSW government has accused the opposition of walking away from talks on water management and rejecting a federal plan for the Murray-Darling river system.

The Liberal-National Party coalition says the Murray-Darling planning process should be reworked with as much weight placed on economic and social factors as on environmental factors.

The opposition also says NSW Water Sharing Plans for the allocation of water between the environment and water users should be extended to coincide with plans adopted in Victoria.

NSW Water Minister Phillip Costa on Thursday accused the opposition of walking away from efforts to resolve the Murray-Darling river system's woes, saying they were "playing politics" over the issue.

NSW split over Murray-Darling plan