Members of the Yinka Dene Alliance, whose territories are along the proposed pipeline, have sent a "cease and desist" letter saying they are opposed to Enbridge seeking temporary permits to conduct preliminary work, including drilling and tree removal.
Alliance spokesperson Jackie Thomas says the company is not authorized to conduct this work on their land.
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"The Joint Review Panel, the National Energy Board, hasn't even finished its report or made any kind of recommendation for this work to go forward," she said.
Thomas says the alliance will first pursue legal action against the company for trespassing.
She says they are also considering physically blocking Enbridge from doing work.
"We've put the RCMP on notice, and expect the police to provide security."
Enbridge spokesman Ivan Giesbrecht says the company is committed to doing this work during the review process.
"This was was the type of information that was asked of us at the joint review panel, and obviously it's a routine part of our project," he said.
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