Enbridge Inc. proposed pipeline tunnel under Michigan’s Straits of Mackinac was approved by a key commission, a win for the company amid a long-running dispute with the state’s governor over the conduit’s future.

The Michigan Public Service Commission approved the company’s application to build a tunnel under the channel that connects Lakes Michigan and Huron. The tunnel would house the company’s Line 5 oil pipeline, which currently rests on the lakebed. Enbridge argues the tunnel will reduce risks of an oil spill but Governor Gretchen Whitmer issued an order to shut the line.

Enbridge and Whitmer have been enmeshed in a court battle for years and the dispute has roiled relations between the US and Canada, which relies on Line 5 to supply refineries in Quebec and Ontario.

“We are ready to begin work on this project,” Enbridge said in a release. “The only thing standing in the way of locating a replacement section of Line 5 into the tunnel is a decision on our permit application by the U.S. Army Corps of Engineers.”

(Adds Enbridge comment in final paragraph)