"Therefore, after robust analysis and discussions and with heavy hearts, we share with you our intention to close our tourism businesses for the time being. This difficult decision has also resulted in a proposal to significantly downsize our Ngāi Tahu Tourism workforce, with more than 300 kaimahi at all levels potentially losing their jobs as a result," they said.
After a full consultation period, a final decision will be made next month.
Proposing the moves was "devastating for us – and certainly something we did not envisage a few months ago".
The business was doing all it could to support those affected and was particularly proud of the whanaungatanga and manaakitanga on display across the organisation in such difficult circumstances, the statement said.
"At this time of challenge for our Ngāi Tahu Tourism kaimahi and our tourism operations, we are reminded of our gratitude for those who led our iwi through Te Kerēme and Settlement.
"Those who came before us have ensured that Te Rūnanga o Ngāi Tahu has a diversified portfolio of business interests, including tourism, seafood, property, forestry, farming and capital investments. This careful and deliberate structure means that when these challenging times come, we can continue our important work of protecting and sustaining the pūtea for future generations," it said.
As the business was undergoing consultation with its kaimahi, it would not be making any further comment, the statement said.
Clutha-Southland MP Hamish Walker said the news was "heart-breaking".
"As one of our large employers here in Queenstown, to see staff lose their jobs is distressing for all involved.
"My heart goes out to all of the people involved, who like so many in our community are now facing even more uncertain times, with no income, " Mr Walker said
Mr Walker said two out three people in Queenstown worked in the tourism sector and if there was not more Government support given soon, it was going to get "far worse before it gets better".
More large scale redundancies would come.
"It's why more needs to be done to support our businesses, so we can support our people in staying in work and getting through this tough time.
"I've spoken with dozens of businesses whose futures are all uncertain and unless they receive some support they will have to close their doors.
"It is trying times throughout New Zealand but Queenstown is by far the worst affected area."