Federated Farmers says a draft policy on water mooted by Environment Minister Nick Smith, amounts to a moratorium on intensive development.
Dr Smith, gave a strong indication on Wednesday that he plans to adopt a tough new policy to clean up polluted rivers.
The policy was recommended by a board of inquiry in February.
But Federated Farmers says farmers strongly oppose the policy.
Dairy chair Lachlan McKenzie says it would mean a moratorium on the expansion of intensive dairying and all other types of development.