On Tuesday, President Barack Obama announced a new round of environmental protections that permanently ban offshore oil and gas drilling across large areas in the Arctic and Atlantic Ocean — continuing his rush to use his last month in power to protect the world from his successor and his oil-loving cabinet.

Obama’s actions are already winning the praise of environmental advocates, but they’re also raising the question of whether they’re merely symbolic gestures or if they can withstand the Trump presidency.

The US, which acted along with Canada, is protecting 115 million acres of federal waters north of Alaska in the Chukchi and Beaufort seas from oil and gas exploration. In order to do this, Obama invoked an ambiguous portion of the Outer Continental Shelf Lands Act, a 1953 law that permits him to independently stop lands from being accessed for drilling. Unsurprisingly, environmental groups have hailed the move as a necessary measure needed to thwart President-elect Donald Trump and his appointees from catastrophically harming one of the most vulnerable areas on the planet.

“The Sierra Club applauds President Obama for taking historical action by answering the calls of coastal communities and millions of people across the country for our oceans to be permanently protected from the threat of offshore drilling,” Sierra Club Executive Director Michael Brune wrote in a statement. “America’s waters are for all of us to enjoy, and they should never be threatened — especially by oil rigs.”

Cathleen Kelly, a Senior Fellow with the Energy and Environment team at the Center for American Progress commended Obama’s move, citing the U.S.’s lack of basic infrastructure and capacity essential for oil spill clean up. “The area in the Atlantic set aside by the president is home to a host of rare corals and fish species,” she told Vocativ in an email. “With Donald Trump’s transition team and cabinet nominees stacked with fossil fuel industry insiders and climate science deniers, the president clearly felt the need to put America’s coastal communities, fisherman, marine life, and beaches ahead of Big Oil interests.”

And yet, Obama has less than a month left as president. His replacement, Donald Trump, at one point accused Obama of doing “everything he can to get in the way of American energy,” and vowed to reverse that course by ramping up domestic energy production. Trump’s secretary of state-designate, ExxonMobil CEO Rex Tillerson, has spent his career in oil production, including pushing for Arctic oil drilling, seems likely to share Trump’s views. But, can the new administration simply roll back these measures?

Sierra Club Senior Press Secretary Jonathon Berman told Vocativ he cannot. “[Tuesday’s] actions are permanent, and neither Trump nor anyone in his administration can undo them,” he said. White House officials also say that Obama’s latest action cannot simply be erased by the incoming president.

However, it is unclear if a Republican-controlled Congress can dismiss Obama’s move, or if it could simply amend the Outer Continental Shelf Lands Act. “There is a precedent of more than half a century of this authority being utilized by presidents of both parties,” a White House aide told The Washington Post on Tuesday. “There is no authority for subsequent presidents to un-withdraw…I can’t speak to what a future Congress will do.”

Kelly also noted that reversing the president’s authority on the matter would not be easy for the Trump administration, legally speaking. “A reversal would require a 60-vote majority in the Senate, which will be a challenge with only 52 seats held by Republicans,” she told Vocativ.