The Government is willing to beef up the powers and role of the second tier of councils under the proposed Auckland super city, Prime Minister John Key said today.

The Auckland governance legislation select committee has begun a marathon session to consider almost 2500 submissions on the Local Government (Auckland Council) Bill.

Mr Key said he was delighted at the number of people getting involved and they would be listened to with an open mind.

"There is now a strong consensus for a single unitary authority for Auckland with the ability to get things done," Mr Key said.

The bill proposes up to 30 community boards under the council, but many have called for fewer bodies in the second tier, but with more powers.

Mr Key said it was always expected there would be debate about the second tier, whether there should be Maori seats and how the councillors on the single unitary authority are elected -- either at large or through a ward-based system.

"I fully expect at the end of the exercise we will see a second tier with beefed up powers that reflect the diverse communities they serve, act on their behalf and preserve their unique identities," Mr Key said.

Labour leader Phil Goff said Labour supported the unitary council, but believed the second tier should be reduced in number and given stronger resources and authority than currently envisaged.

The Government has already passed under urgency a law setting up the concept of a council and a transition agency to manage local affairs.