MINNEAPOLIS (AP) — The U.S. Interior Department said Wednesday it has reinstated the mineral rights leases for a company that wants to build a copper-nickel mine near Ely in northeastern Minnesota, reversing a decision to deny the renewals that was made in the closing weeks of the Obama administration.

The department's Bureau of Land Management informed Twin Metals Minnesota of its decision in a letter Wednesday, company spokesman Bob McFarlin said. The move followed a legal opinion from the department's solicitor last December that concluded that Twin Metals has the right to renew its two leases, which date back to 1966.

President Barack Obama's administration had cited the potential harm from acid mine drainage to the Boundary Waters Canoe Area when it declined to renew the leases in December 2016, dealing what could have been a fatal blow to the project. The proposed mine site sits in a watershed that flows into the pristine wilderness area.

In a statement, Twin Metals said the company was pleased with the department's action, calling it "an important step in the lease renewal process." Twin Metals said the reinstatement also will allow the company to resume environmental study and project development activities on the federal leases this summer.

Interior Department Press Secretary Heather Swift confirmed the decision in an email to The Associated Press. She wrote that the reinstated leases will remain in effect until the bureau formally acts on Twin Metals' lease renewal application, and that it will be "subject to reasonable updated terms and conditions." Twin Metals can now resume exploration activities, she said, but the decision doesn't authorize the company to begin mining.

U.S. Rep. Tom Emmer, who authored legislation that passed the House to direct the bureau to renew the leases, welcomed the decision. He issued a statement calling it "another step to full restoration of our state's right to explore and advance reasonable mining."

But Northeastern Minnesotans for Wilderness and its partners in the Campaign to Save the Boundary Waters plan to challenge the decision in court, Doug Niemela, the group's executive director, said in a statement. He said the department failed to consider the environmental damage of developing a large mining district on the edge of the Boundary Waters.

Any mining on the site near Birch Lake would be years away. Twin Metals, which is owned by Chilean mining company Antofagasta PLC, has yet to submit a formal mining plan, which would have to go through an extensive environmental review.