The Tuhourangi Tribal Authority wants to know why the Te Arawa federation did not know about a potential tourism deal in Rotorua ahead of Ngai Tahu.
The South Island iwi has confirmed discussions have taken place with the owners of the Rotorua Agrodome, which offers entertainment related to New Zealand agriculture such as sheep shearing and sheep dog demonstrations.
Tuhorangi chairperson John Waaka says "good on Ngai Tahu" for doing the best for its shareholders.
But he is disappointed the commercial arm of Te Arawa trust - Te Arawa Group Holdings, didn't know about the opportunity.
Te Arawa Group Holdings manages treaty settlement assets on behalf of 11 Iwi and hapu.
Chief executive of Te Arawa Group Holdings Roger Pikia says the company was not aware of the discussions.
He says businesses like the Agrodome hold talks with whoever they want.
Mr Pikia says Ngai Tahu has just as much right as other businesses or nationalities to do business in the region.