Whanau Ora Minister Tariana Turia has defended a change in how the scheme's funding is controlled, saying non-Government organisations know what's needed better than the bureaucracy in Wellington.
The Government on Tuesday announced the private sector will be given the responsibility of allocating tens of millions of taxpayer dollars in Whanau Ora contracts from 2014.
The social service scheme funds providers to deal with the needs of families as a whole rather than than through different welfare agencies.
At present, Whanau Ora receives on average $40 million of government funding each year. That will be handed to three non-governmental commissioning agencies, to be set up from within the community sector. One will be for the North Island, one for the South Island and one for Pacific Island communities.
Labour and New Zealand First say they are worried that control of large amounts of money will be taken away from the Government and put in the hands of private agencies.
Mrs Turia told Radio New Zealand's Morning Report programme that agencies outside Government know better what is needed to help local communities achieve their goals.
"All the decisions are made down here in Wellington. That isn't good. What we want to see is communities being able to stand up and say what's important for them."
Mrs Turia says the first taskforce on Whanau Ora, which came together under Sir Mason Durie, recommended the control of contracts should not go to a Government agency.
Listen to Tariana Turia
Labour pledges to reverse changes
The Labour Party says if elected to Government it would pull control of Whanau Ora funding back to the Ministry of Maori Development (Te Puni Kokiri).
Labour's social development spokesperson, Jacinda Ardern, says the party supports the principle of Whanau Ora, but taking the commissioning away from the Government is not the way to go.
"The principle of Whanau Ora is very difficult to argue with - why wouldn't we want to co-ordinate government agencies ... but to make sure we're doing that surely that means Government has to keep a seat at the table. I'm concerned that this announcement looks like it's cutting them out."
Green Party co-leader Metiria Turei says Whanau Ora needs more time to bed in before responsibility for allocating contracts is transferred.
"I think it needs to be running effectively, it needs to be well monitored, it needs to have widespread support amongst Maori before changing the model to something different.
"What this is more likely to have happen is that there'll be greater gaps ... between how services are delivered, who's getting access to them, the criteria, how that's being evaluated, how it's being monitored."
New Zealand First leader Winston Peters says putting control of Whanau Ora's funding into the hands of private commissioning agencies, means it is not subject to the Official Information Act.
Mr Peters says he has never supported Whanau Ora, and now it appears it will not be open to public scrutiny.