Yukon Premier Sandy Silver says the federal government should not have rejected an environmental assessment prepared by territorial officials.
The Yukon Environmental and Socio-economic Assessment Board released its recommendations for BMC Minerals' proposed Kudz Ze Kayah lead-zinc-copper-gold mine in October.
It stated there could significant adverse effects from the mine, located 115 kilometres south of Ross River in southeast Yukon, but the effects could be mitigated by following 30 recommendations in its assessment.
Officials with Fisheries and Oceans Canada and Natural Resources Canada, however, referred the assessment back to the board for reconsideration.
In a letter to the assessment board, the federal government officials said the board's review needs more detail about how the effects will be mitigated.
Those effects include water quality, wildlife, particularly the Finlayson Caribou Herd, and traditional land use by Kaska citizens.
The federal officials say the assessment board also failed to properly address concerns from the Ross River Dena Council and the Liard First Nation. They also want to know how Aboriginal rights were incorporated into the board's recommendations.
"The Screening Report and Recommendation does not expressly delineate whether and how First Nation interests, including from a (Indigenous) rights perspective, have been considered within the assessment," the officials' letter to the Yukon assessment board says.
The letter noted the Ross River Dena want more discussions on how the recommendations will be implemented. And the Liard First Nation does not believe the mitigation measures will protect its members' right to hunt the Finlayson Caribou Herd.
Liard First Nation chief Stephen Charlie said Tuesday the recommendations should not be approved until they're acceptable to the Kaska people.
Premier Sandy Silver, however, said in a written statement that the assessment board's review was comprehensive and the recommendations reasonable.
The decision by the federal government, "creates unreasonable and unnecessary uncertainty for the proponent and sends a troubling signal," Silver said.
"The government of Canada absolutely needs to take steps to streamline these processes going forward to ensure greater clarity and certainty for the mining industry."
Silver said the territorial government was prepared to issue a decision accepting the recommendations.