TransCanada Corp. (TRP.TO) is hoping to start construction by June on its decade-old Keystone XL oil pipeline project, even as the U.S. government shutdown threatens to delay a key legal proceeding.

In a court filing on Monday, the Calgary-based pipeline company said its current schedule requires pre-construction activities including setting up pipe yards and work camps to resume by February. That would allow full work to begin by June and be completed in late 2020, with the pipeline entering service in early 2021.

TransCanada reiterated that a yearlong delay would cost the company US$949 million in lost profits and delay the hiring of about 6,600 workers. The company would also face higher construction costs as competition for crews increases in 2020, TransCanada said in a letter filed in U.S. District Court in Montana.

The 1,200-mile (1,900-kilometer) pipeline, which would help carry 830,000 barrels of crude a day from Alberta’s oil sands to U.S. Gulf Coast refiners, has faced legal holdups amid staunch opposition from environmental groups and landowners.

The same court last month sided with environmental groups opposing the project and said TransCanada couldn’t resume field work while it awaited a new environmental review from the U.S. State Department. Prior to that ruling, TransCanada had hoped to start construction as early as mid-February.

A hearing is scheduled for Jan. 14, though the Justice Department -- which is representing the State Department in the proceedings -- lacks funding due to the partial government shutdown. TransCanada asked the court to move forward with that hearing without the Justice Department, a move the agency supported in a separate letter.