Attorney-General Chris Finlayson concedes that specifically banning access charges to areas held under Maori customary title will create an anomaly under the law.
The Government is likely to amend the marine and coastal area legislation to prevent those holding customary title charging fees for access to the foreshore and seabed.
The Maori Party says that is unfair, as other private land owners can charge what they like.
The party says iwi have already promised free access, and having a fee ban spelt out in the law is an affront to Maori.
The Government acknowledges the legislation will impose different requirements on different groups of New Zealanders.
But it says the amendment is aimed at removing any doubt about the public's right to access to coastal areas.
Law change insulting - Sharples
The Maori Party says the law change that will specifically ban Maori customary title holders from charging public access fees is insulting.
The ACT Party has been lobbying for the change, saying it will be good to have the ban on access fees specifically put into the legislation.
Maori Party co-leader Pita Sharples says Maori have already promised free public access, and ACT's push to have it spelt out in the law is an affront to iwi.