An iwi group that has already settled its Treaty claim in the Wellington area says it should have been consulted over the terms of a rival iwi's upcoming settlement.

The competing claims of Taranaki Whanui and Ngati Toa have been before the High Court at Wellington this week.

Ngati Toa hopes to sign off its agreement with the Crown in early December. Its lawyer, Bridget Ross, said in court yesterday that it was 23 years since Ngati Toa registered its claim with the Waitangi Tribunal and seven years since it began negotiating a settlement with the Crown.

Taranaki Whanui, a grouping of Taranaki-based tribes who were established in the Wellington area at the time the Treaty of Waitangi was signed in 1840, settled their claim in 2009 under the name of the Port Nicholson Block Settlement Trust.

The grouping says it has a better claim than Ngati Toa to some forms of cultural, as opposed to commercial, redress, including the 2.5-hectare Taputeranga Island at Island Bay.

It says it was told it could not have the island because it was in the hands of Wellington City Council, only to find out later that it was included in the Ngati Toa settlement deal.

"It is cultural redress of the very kind that Taranaki Whanui sought and was denied," lawyer Phillip Green said.

Both groups say they have a legitimate historical claim to the island.

Taranaki Whanui took the Crown to court to argue that it should have been consulted about the Ngati Toa settlement. Ngati Toa was joined as a party to the case at its request, and Miss Ross said it was a rare thing for Ngati Toa to find itself on the same side as the Crown.

The Crown's lawyer, Paul Radich, said the Crown had to reserve itself the ability to settle overlapping claims and, in any event, it had consulted Taranaki Whanui about the Ngati Toa settlement.

The Taranaki Whanui settlement did not include an exclusive claim to areas in which it had a dominant interest in 1840, Mr Radich said.

Justice Joe Williams, a former chairman of the Waitangi Tribunal, said he would try to decide the case by the end of next week.

He heard argument that included what expectations Taranaki Whanui could legitimately have to be consulted about Ngati Toa's later settlement, and who would be most prejudiced if he made orders that Taranaki Whanui should be consulted.

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