Some iwi and hapu may not be willing to put their own negotiations on hold to allow a pan-Maori body to negotiate water rights with the Crown.
At a national hui last week called by King Tuheitia, a resolution was passed to determine proprietary rights before any individual talks with the Crown about asset sales.
Maori Council deputy-chair Rahui Katene says that though most iwi and hapu are supportive, some may not want to get behind a single body to negotiate water claims with the Crown.
"There may be some that want to do it in a different way. That's entirely up to them. It's all about rangatiratanga after all, and we're not there to dictate to anybody or tell them what they should do.
"But overwhelmingly the message to the Crown is that we are united and will continue to be united, and this is what we think should be happening."
She says the Government should not be allowed to shift the ground for consultation onto individual claimants and ignore question of proprietary rights for all Maori.
Council co-chair Maanu Paul says it would be disturbing if some tribes pursued their own claims because it's only through being united that they can be sure of winning their cause.
Mr Paul says if Prime Minister John Key continues to ignore the Waitangi Tribunal's ruling on the need to consult over water rights the council will go back to court.
Iwi Chairs Forum spkesperson Tom Roa says tribal leaders have agreed they want to present a united front but still have to work out the mechanics of that.
PM confident of privatisation plan
Prime Minister John Key says differences of opinion among Maori will not alter the Government's approach to negotiating with iwi over water.
Mr Key says he has told the Maori Council he will not negotiate with them, but will talk with specific iwi on the narrow point of offering special shares to them, a concept raised by the Waitangi Tribunal as 'shares-plus'.
Mr Key told Morning Report the Government has said it does not see merit to the shares-plus argument, though he said the idea has not yet been analysed well enough.
He has asked officials to study it further and is confident anything they come up with could be implemented after partial privatisation.
The Government this month delayed the sale of up to 49% of shares in the Mighty River Power until next year, after an interim report from the Waitangi Tribunal found that Maori have proprietary rights over water.