Ngatiwai Trust Board chairman Haydn Edmonds said the body was still processing the information in the report.
"We believe the Deed of Mandate we have established clearly provides for kaumatua, hapu and marae representatives to advise the board at a governance level," Mr Edmonds said.
"We understand and recognise there are still some members and, in particular, three hapu who have concerns about what the mandate means for them. We have been working through this issue since it was first raised and will continue to hold hui to enable them every opportunity to engage with us in this settlement process."
Te Kapotai spokeswomanWillow-Jean Prime said it opposed the mandate, as the hapu never consented to being included in it.
"We have never given our consent, so we're really pleased the tribunal has granted this hearing."
It's not the first time an iwi's Deed of Mandate has been challenged. Tuhoronuku's mandate to negotiate on behalf of Ngapuhi saw several hapu lodge applications with the Waitangi tribunal for urgency hearings.
As a result, a report by the tribunal found, while Tuhoronuku's mandate was legitimate, their structures undermined the sovereignty of hapu.
Ms Prime said there were parallels between Tuhoronuku's mandate and the Ngatiwai Trust Board's mandate and the Crown needed to reconsider the way the mandating process was carried out.
"The focus is on these large natural groupings when it should be on hapu."
The Minister of Treaty Negotiations, Chris Finlayson, had no comment to make as the issue was currently before the tribunal.