Auckland's mayor is not ruling out a charge for motorists travelling within congested areas in order to fund a 30-year public transport plan.
Last week, the Auckland Council made public its vision for the region, including a rail loop in the central city.
It issued a discussion document which mentioned congestion charging, tolls, a regional fuel tax and levies on private parking as possible ways of funding new public transport infrastructure.
The Automobile Association says it is concerned drivers will be hit with new taxes and charges to pay for the public transport project.
The association says motorists already subsidise public transport and are hurting from high fuel costs.
It believes the discussion document mentions critical gaps in roading infrastructure if the council proceeds with plans for three rail lines.
Mayor Len Brown told Morning Report on Monday there will be significant public discussion before any decisions, including on congestion charges, are made.