Attorneys for the U.S. Justice Department on Monday urged U.S. District Judge Richard Leon to throw out a lawsuit that seeks to overturn the administration's decision.
The March cancellation of a 6,200-acre energy lease near Glacier National Park has been assailed by the oil and gas industry and the U.S. Chamber of Commerce.
Business groups say the administration's move set a precedent that will discourage development if not overturned. A Louisiana company held the lease for 33 years but had yet to drill.
The lease is in northwestern Montana's Badger-Two Medicine area, location of the creation story for the Blackfoot tribes in Montana and Alberta.