Before leaving office, President Barack Obama has taken one more action in his efforts to combat climate change by banning oil exploration across much of the Arctic and a stretch of sea canyons in the Atlantic Ocean, according to a report from BuzzFeed.

The offshore oil drilling ban was issued by Obama in partnership with Canadian Prime Minister Justin Trudeau as a part of an order that will protect about one quarter of the Arctic waters from oil drilling, including offshore areas in northern Alaska and the Canadian Arctic. The U.S. block exploration at 31 undersea canyons and will prevent drilling across 3.8 million acres of federal waters.

The orders from the two North American countries will also set up safe shipping lanes across the Arctic, allowing passage through the area—a feat that is possible thanks to the ongoing melting of the Arctic ice cover.

Canada’s ban will require a review every five years. The U.S. ban will be in place “indefinitely,” though may be at risk of reversal under President-elect Donald Trump, who has promised to expand oil exploration and named Exxon Mobil CEO Rex Tillerson as his Secretary of State.

“President Obama and Prime Minister Trudeau are proud to launch actions ensuring a strong, sustainable and viable Arctic economy and ecosystem, with low-impact shipping, science based management of marine resources, and free from the future risks of offshore oil and gas activity,” the world leaders said in a statement. “Together, these actions set the stage for deeper partnerships with other Arctic nations, including through the Arctic Council.”

The action comes after a considerable push made by environmental groups and a collection of 14 Democratic senators. The group was led by Senator Ed Markey of Massachusetts, who issued a letter to President Obama in October asking the commander-in-chief to place a ban on oil and gas leases in federal waters.

According to Markey’s letter, the ban issued by President Obama would be permanent and wouldn’t be subject to reversal under the incoming administration.