Auckland mayor Len Brown says local-government reform proposals seem to clash directly with the council's legislation.
New legislation to be introduced in Parliament in May will require councils to have a tighter focus and be more transparent about their finances.
Local Government Minister Nick Smith wants them to move away from promoting social, cultural and environmental well-being and focus on infrastructure and public services.
Dr Smith will begin meeting mayors and council chief executives on Tuesday to discuss the changes.
Mr Brown told Morning Report on Tuesday the Auckland Council must establish a spatial plan that encompasses those important issues.
"What was the purpose of us coming together," he says, "if we weren't going to really deal with the fact that the country wants Auckland to be much stronger, an economic powerhouse of the nation?"
'Already fiscally responsible'
Mr Brown says the council is already being fiscally responsible, and has just received an AA rating from the international ratings agency Standard and Poor's.
He says the Government's proposals are being fully assessed before the council comes to a final opinion.
However, Dr Smith told Morning Report the Auckland Council is doubling up in a number of areas, including setting NCEA pass rates and greenhouse gas targets.
"I think they are the sorts of nonsense areas where I am wanting to say to councils: your job is not to replicate the private sector, it is not to replicate what is provided by the Government; your job is is to focus on those things that only councils are able to provide."
Dr Smith says the local body changes will build on the reforms made in the Auckland supercity amalgamation.
Local Govt NZ wants more detail
The body representing local councils says it is largely supportive of changes proposed by the Government, but it needs more detail.
Chairperson Lawrence Yule says it has been asking the Government for some time to look at councils' obligations in some areas.
He says they have often taken over functions - particularly in social areas - because the Government has failed.
Mr Yule says New Zealand needs to have a serious conversation about what infrastructure is needed and how it is funded.
Chamber executive backs moves
The chief executive of the Auckland Chamber of Commerce, Michael Barnett, is backing the Government's move to rein in the scope of local councils.
Mr Barnett says the burden of rates for households is now much higher than it used to be, and he does not believe it is wrong for the Government to want to limit councils' involvement in events such as V8 supercars.
The director of AUT's Local Government Centre, Peter McKinlay, believes however that the reforms could harm economic development if there is a perception that quality of life is reducing.
Mr McKinlay says New Zealand already has a hard time attracting the people it needs.