East Coast iwi Ngati Porou says classifying the seabed and foreshore as public domain will help iwi negotiate for customary rights.
Prime Minister John Key says if the Maori Party does not support the proposal to deem the foreshore and seabed public domain, then the existing law will stay.
Iwi Leaders Group chair Mark Solomon says it would be unfair to force this on iwi and hapu, when there are 12,500 private land titles with seabed and foreshore rights.
But Ngati Porou chair Apirana Mahuika told Morning Report the public domain suggestion will help iwi.
He said iwi leaders had not rejected the public domain suggestion.