Ngāi Tahu are calling on Rio Tinto to engage with iwi over the closure of the aluminium smelter at Tiwai Point.
Earlier this year Rio Tinto announced its intention to exit Tiwai Point in August next year.
The government has stepped in to negotiate a delay to the closure and during the election Labour campaigned on a Just Transition for the Southland region with the deadline for closure extended to three to five years.
Last week ministers briefed the region's mayors on the ongoing negotiations with Rio Tinto.
But there is another voice that wants to be heard at the table.
Te Runaka o Awarua Upoko, Sir Tipene O'Regan, last week wrote a letter to the chairman of Rio Tinto Group expressing Ngāi Tahu's interest in the matter.
In the letter Sir Tipene laid out the iwi's interest as tangata whenua of the takiwā within which Tiwai Point and New Zealand Aluminium Smelters operations sit.
"The purpose of this letter is to open a dialogue with you and your board," Sir Tipene wrote to Simon Thompson.
"Your company website states that part of your sustainability programme is to negotiate agreements with Indigenous peoples, local communities, and others to demonstrate respect and commitment to inclusive engagement with communities and land connected peoples that may be affected by your operations.
"This goes to the essence of the principles of kaitiakitanga (guardianship and stewardship), so we wish to engage with you to discuss our mutual obligations to reduce the potential effects of the closure of the Tiwai Smelter, both on our community and our environment.
"We would hope that an outcome of such engagement would be agreement on the future of the smelter and the Tiwai Point site. At the outset we wish to acknowledge the historically amiable interaction between our Awarua Runaka and NZAS over the past decades of operation at Tiwai."
Concerns about site remediation
Sir Tipene told RNZ there were concerns about how the site would be remediated once the smelter's operations cease.
"We are concerned about that prospect and we are seeking to engage with them to discuss it and in fact support the position that the government has been taking with them of not backing down on a half-hearted sort of a job there.
"We're very supportive of the position the ministers responsible have been taking thus far on the question of remediation."
The iwi also had concerns about the economic effect of the closure and what could be done to mitigate it, and had ideas for future sustainable economic use of the site, Sir Tipene said.
In a statement, New Zealand Aluminium Smelters chief executive Stew Hamilton said: "We are proud of our long standing relationship with Te Ao Marama and recognise Ngāi Tahu as mana whenua of Tiwai Point and we look forward to continue working with them on our closure planning process".