Treaty lawyer Annette Sykes says the Crown is paying $300,000 to large iwi to receive advice on freshwater issues - but smaller tribes do not see a cent or get the support.
Ms Sykes has been before the Waitangi Tribunal hearing into water rights, representing her claimants.
Ms Sykes says the Government is choosing to deal with the Iwi Leaders Forum on freshwater.
But she says it is an exclusive group and only a handful of iwi get a direct line to the Government.
She describes them as the super iwi structure: Te Arawa, Tuwharetoa, Whanganui, Waikato-Tainui and Ngai Tahu.
She says representatives of those iwi get exclusive access to Prime Minister John Key - and get exclusive funding.