The Government has postponed a proposed Treaty of Waitangi settlement that would have returned most of an ecological reserve in Waikato to Maori.
The dispute centres on the Maungatautari Ecological Reserve near Cambridge.
Landowners are upset at changes to how the sanctuary is governed and want a structure that is one third iwi, one third community and one third landowners reinstated.
The year-long row has led to landowners threatening to cut a 47km- long pest-proof fence surrounding the sanctuary.
The Maungatautari Landowners Council is also opposed to local Maori being given 2500 hectares of the reserve in the Treaty settlement.
A negotiator for Ngati Koroki Kahukura, Willie Te Aho, told Waatea News the settlement was supposed to be signed on Monday.
However, Mr Te Aho says Treaty Negotiations Minister Chris Finlayson has told them that retired High Court judge Sir David Thompkins, QC, is now looking into landowners' concerns.
The landowners are supported by financial adviser Gareth Morgan.
"We were somewhat upset because it's a minority of four farmers and a millionaire behind them.
"That's actually going contrary to not only the iwi, but the Maungatautari Ecological Island Trust and the bulk of the community that are in support of both the ecological island and the Treaty settlement."
Mr Te Aho says the iwi is still committed to getting legislation that protects the special character of the bush-clad mountain.
The Maungatautari Landowners Council says a meeting with Waipa mayor Alan Livingston on Friday over the governance issue was unsatisfactory and the group still plan to tear the fence down.