National would amend Labour's controversial foreshore and seabed legislation to "give protection to all New Zealanders' interests", Don Brash has said.
In his latest condemnation of the law, Dr Brash said National would also remove the jurisdiction of the Maori Land Court to hear claims for the foreshore and seabed.
The party leader made the comments at a public meeting at Ohope Beach School hall in the Eastern Bay of Plenty.
Under National, rangatiratanga (authority) and kaitiakitanga (guardianship) would not be an appropriate basis for a customary use-rights claim.
The Maori Land Court chief judge Joe Williams recently agreed to hear a claim from a small Opotiki iwi for control of a 50km stretch of Eastern Bay of Plenty coastline.
The claim by Whakatohea seeks a customary rights order over the tract of coastline from Te Horo, near Whakatane, to Te Rangi, near Torere.
Whakatohea is claiming rangatiratanga and kaitiakitanga over the stretch.
The hapu has to show it has continually exercised authority and guardianship over the coastal area since the Treaty of Waitangi was signed in 1840.
Maori have welcomed the judge's willingness to hear the application, which is the first under the Foreshore and Seabed Act.
Maori Party leader Pita Sharples said a "barrage of applications" could follow if it is successful.
Dr Brash last night said a large number of claims would create years of litigation and ongoing dispute.
"National would amend the legislation to give protection to all New Zealanders' interests."
He said Labour was not dealing with the issue of what would happen if the claim was successful.
"They are clearly happy to leave this issue to the Maori Land Court."
Success could give the hapu veto over applications under the Resource Management Act, he said. Fishing rights would also likely be affected.