The Red Lake and White Earth Bands of Chippewa asked the independent Public Utilities Commission to stay its earlier approval of the project, citing pending litigation before the Minnesota Court of Appeals.
Attorneys for the two northern Minnesota tribes argued that allowing construction to continue would cause irreparable harm should the court rule in their favor.
“Without a stay, Line 3 would be constructed before the court could determine if the PUC broke the law, making the case moot," LaDuke said in a statement.
Line 3 begins in Alberta, Canada, and clips a corner of North Dakota before crossing Minnesota on its way to Enbridge’s terminal in Superior, Wisconsin.
The replacement segments in Canada, North Dakota and Wisconsin are already complete, leaving only the 337-mile (542-kilometer) stretch in Minnesota.