Invoking a 1953 law governing the Outer Continental Shelf (OCS), President Barack Obama on Tuesday said he would withdraw vast areas in the Arctic and Atlantic oceans from future oil and natural gas drilling.

Simultaneously, Canadian Prime Minister Justin Trudeau said his country would designate all Arctic Canadian waters as indefinitely off limits to future offshore Arctic oil and gas licensing, to be reviewed every five years through a climate and marine science-based life-cycle assessment.

“Today, 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,” according to a joint statement from the leaders. “Together, these actions set the stage for deeper partnerships with other Arctic nations, including through the Arctic Council.”

The withdrawal areas announced by Obama encompass 3.8 million acres in the north and mid-Atlantic Ocean off the East Coast and 115 million acres in the U.S. Arctic Ocean, according to the Department of Interior. In the Atlantic, the withdrawal decision protects 31 canyons, extending from Heezen Canyon offshore New England to Norfolk Canyon offshore of the Chesapeake Bay. The Arctic withdrawal encompasses the entire U.S. Chukchi Sea and significant portions of the U.S. Beaufort Sea.

The withdrawal does not restrict other uses of the federal waters on the OCS and will help to sustain commercial and recreational fisheries in the Atlantic to support fishing-dependent communities, as well as the harvest of marine resources on which many Alaska Native communities rely for subsistence use and cultural traditions, according to U.S. Secretary of the Interior Sally Jewell.

“The president’s bold action recognizes the vulnerable marine environments in the Arctic and Atlantic oceans, their critical and irreplaceable ecological value, as well as the unique role that commercial fishing and subsistence use plays in the regions’ economies and cultures,” Jewell said. “The withdrawal will help build the resilience of these vital ecosystems, provide refuges for at-risk species, sustain commercial fisheries and subsistence traditions, and create natural laboratories for scientists to monitor and explore the impacts of climate change.”

The withdrawal does not affect existing leases and would not affect a nearshore area of the Beaufort Sea, totaling about 2.8 million acres, that has high oil and gas potential and is adjacent to existing state oil and gas activity and infrastructure, DOI said. That area will be subject to additional evaluation and study to determine if new leasing could be appropriate at some point in the future. Interior’s five year offshore leasing program for 2017-2022 does not include lease sales in either that area or in the withdrawn areas, the agency said.

“Risks associated with oil and gas activity in the remote, harsh and undeveloped Arctic are not worth taking when the nation has ample energy sources near existing infrastructure,” said Abigail Ross Hopper, director of DOI’s Bureau of Ocean Energy Management. “Oil spill response and clean-up raises unique challenges in the Arctic and a spill could have substantial impacts on the region, particularly given the ecosystem fragility and limited available resources to respond to a spill.”

Last month, the Obama administration removed the Beaufort and Chukchi seas from its five-year offshore oil and gas leasing program but kept 10 potential lease sales in the Gulf of Mexico (GOM) and one in Alaska’s Cook Inlet. A draft version of the 2017-2022 leasing program, containing 14 potential lease sales in eight planning areas, was unveiled in January 2015. The draft version included 10 potential lease sales in the GOM, three in offshore Alaska (one each in the Beaufort and Chukchi seas and the Cook Inlet) and one in the Atlantic Ocean, covering areas offshore Virginia, North Carolina, South Carolina and Georgia. After receiving criticism from coastal communities and the military, the Obama administration removed the Atlantic sale from the program last March.

Alaska Gov. Bill Walker blasted the restrictions of waters off Alaska. “This unprecedented move marginalizes the voices of those who call the Arctic home and have asked for responsible resource development to lower the cost of energy to heat houses and businesses. For centuries, the Arctic has provided food for those in the region. No one is more invested than Alaskans to ensure that the habitats within the Arctic are protected.

“To lock it up against any further exploration or development activity is akin to saying that the voices of activists who live in Lower 48 cities have a greater stake than those to whom the Arctic is our front yard and our back yard,” Walker said. He noted that at his urging certain areas were left out of the ban, but no lease sales have been scheduled for those areas through 2022.

Industry representatives were also critical of the announcement.

“President Obama is doing a great disservice to this country by putting the demands of special interest activists above the interests of the American people,” said Chris Warren, spokesman for the American Energy Alliance. “These offshore areas belong to the public and should be used to their benefit — not to further the president’s keep-it-in-the-ground political agenda.”

But environmental groups were quick to praise the joint U.S.-Canada announcement.

“President Obama has taken a key step in protecting important areas of the Atlantic Ocean from offshore drilling. In doing so, he is making a good decision — a smart business decision — based on science and facts,” said Jacqueline Savitz, Oceana’s senior vice president for the United States. “This decision will help protect existing lucrative coastal tourism and fishing businesses from offshore drilling, which promises smaller, short-lived returns and threatens coastal livelihoods. The people of the Atlantic coast refused to allow their way of life to be compromised and we commend their hard work making their voices heard in Washington.”

The announcement comes on the heels of an oil and natural gas lease sale conducted last week by the Alaska Department of Natural Resources that garnered $17.8 million for acreage in the North Slope Foothills.

A recent public opinion poll commissioned by the Arctic Energy Center (AEC) found that 76% of Alaskans support offshore resource development in the state, according to AEC spokesperson Lucas Frances.

“The administration has always justified a ban on Arctic development because of an alleged lack of local support or industry interest. The Arctic Energy Center’s research categorically shows that that is simply not true, with almost three quarters of Native respondents supporting offshore energy,” Frances said. “Taken with last week’s news that sales of Beaufort Sea and North Slope leases generated $18 million, it is hard to avoid the conclusion that the Obama administration is playing politics with the future of Alaska.”