Government lawyers go to federal court Tuesday to seek dismissal of a lawsuit by developers of the proposed Twin Metals copper-nickel mine who are seeking to regain their mineral rights leases.

The Obama administration last year declined to renew the longstanding leases that Twin Metals needs for the underground mine near Ely in northeastern Minnesota. The government cited the potential harm to the nearby Boundary Waters Canoe Area Wilderness.

Twin Metals sued last fall to get those leases back, saying it has already invested $400 million, while its congressional supporters are trying to persuade the Trump administration to reverse that decision.

The government argues that the U.S. District Court for Minnesota should dismiss the lawsuit because it's a contract dispute that must be brought in the Court of Federal Claims.