The Council of Yukon First Nations says it is opposed to all hydraulic fracturing, a method used in oil and gas exploration and extraction.
This year's general assembly passed a resolution which declares traditional territories to be ‘frack free’.
The resolution was brought forward by the Na-cho Nyak Dun First Nation, and passed unanimously. It calls on the Yukon government to prohibit fracking.
In her re-election address, Grand Chief Ruth Massie said environmental protection is a core value for Yukon First Nations.
"I pledge to continue to protect our inherent rights, our land, our water, our environment as our ancestors would have wanted," she said.
The resolution is being welcomed by one environmental group. Don Roberts, who chairs Yukoners Concerned about Oil and Gas Development, said the council is a powerful ally
"This is a game-changer," he said. "The First Nations are there to protect the land, protect the environment."
Roberts and the council both say the practice is too wasteful and too risky.
"The basic issue is water. It takes millions of litres of water to do this process and it poisons the land and it poisons everything around you," said Roberts.