The Automobile Association and the Road Transport Forum want a diesel excise tax introduced, to replace Road User Charges.
A review of the charges was issued on Wednesday. It recommends axing the annual licence fee and replacing it with a more expensive Road Network Access Fee.
Transport Minister Steven Joyce says there won't be any dramatic changes for individual groups of users.
The Motor Trade Association says drivers of new fuel-efficient diesel vehicles are paying road user charges which are equivalent to those charged for diesel trucks. It says that is unfair.
However, the Automobile Association says a diesel tax is the option preferred by the AA and the Road Transport Forum.
