Treaty of Waitangi Negotiations Minister Chris Finlayson says he is not "straightjacketing" Northland hapu into the country's largest iwi, Ngapuhi, in order to reach settlement sooner.
Treaty lawyer Joshua Hitchcock, who has worked on the Ngapuhi claim, says hapu are being grouped with its runanga, Tuhoronuku, when they don't want to be.
He says this is causing in-house fighting and the Crown should back off.
Mr Finlayson will advertise a revised deed of mandate in June and call for submissions.
He says he can't settle with individuals and such problems will arise when bringing together the mandate for Ngapuhi.
The minister says if a case is made out that someone wants to proceed individually, then he will consider that - but it is not going to be discussed over another 25 years.
Mr Finlayson says he is not sacrificing quality by using speed.