The Waitangi Tribunal is warning there's too much uncertainty about the government's proposed Maori land reforms for them to proceed.
It released a lengthy report on the ramifications of the Te Ture Whenua Maori Bill on Friday after releasing a chapter of report last month.
A new round of consultation is under way throughout the country about reforms to the Ture Whenua Maori Act but they are controversial.
Minister of Maori Development Te Ururoa Flavell says it'll be easier for Maori landowners to better utilise their land but many Maori are concerned.
The bill depends on a Maori Land Service but doesn't give enough detail how it will operate or be funded, the tribunal says.
"We found that Maori will be unable to offer properly informed, broad-based support for the bill to proceed, as Treaty principles require."
The Maori Land Service will provide a new administrative framework for Maori land, perform both existing services of Maori landowners and assume new responsibilities.
A Maori enablers workflow will also address long-standing constraints with developing Maori land.
The tribunal says some of the issues the enablers are expected to address are actually Treaty issues while others, like access to development finance, aren't tackled.
"We found that such fundamental reform on the Maori land regime is too important to proceed with without further certainty on all of its components," the report says.
It wants the Crown to avoid compulsion and situations where small groups of Maori landowners alienate the interests of others. It made some detailed recommendations to avoid such situations.
Mr Flavell has said significant changes were made to the bill late last year as a result of written submissions and feedback from nationwide hui.
The bill is expected to be introduced into parliament in March.