Crown Maori Relations Minister Kelvin Davis is adamant a new unit being set up to oversee the public services' work with Māori doesn't duplicate what the existing ministry is doing.
The National Party yesterday described the mandate for the newly-announced Office for Māori-Crown Relations as "vague and unnecessary".
The new agency, Te Arawhiti, announced yesterday, was created to ensure the government met its Treaty of Waitangi obligations.
Mr Davis said the agency was the next step in the Treaty relationship, moving beyond the settlement of Treaty grievances into "what it means to work together in partnerships".
Mr Davis said the move would bring a sharper focus and efficiency to the government's work with Māori.
National's Crown-Māori Relations spokesperson Chris Finlayson yesterday said the agency would overlap with Te Puni Kōkiri, which already provided guidance to the government about policies affecting Māori .
But Mr Davis told Morning Report Te Puni Kōkiri's work "was not organised or complete enough" and that Te Arawhiti's role was focused on a wide-ranging response to Māori needs across the public sector.
"The Ministry of Māori Development, Te Puni Kokiri, work to strengthen Māori capacity and capability and Te Arawhiti will work with public service to strength the government's capacity to deal and work alongside Māoridom," he said.
He said the difference between the two agencies would be "significant" as the new framework and guidelines within the public sector it offered would allow government "to measure the health of relationship between the Crown and Māori".
A business case needed to be developed, but Mr Davis said he hoped Te Arawhiti could be up and running by the end of the year.
He said it would be a small agency with "fewer than most" staff, but rejected the notion that amounted to tokenism.
Several government units and offices will be consolidated into the agency, including the Crown/Māori Relations Unit, the Office of Treaty Settlements, the Marine and Coastal Area (Takutai Moana) Team and the Settlement Commitments Unit.
It would sit within the Justice Ministry, but its chief executive would report directly to Mr Davis.