US President Joe Biden on Friday signed proclamations that will restore the protection of two large national monuments in the state of Utah, as well as a vast marine conservation area.
"These protections provide a bridge to our past, but they also build a bridge to a safer, more sustainable future," Mr Biden said during a ceremony at the White House on Friday afternoon.
He connected the actions he was taking to his administration's work in addressing the climate crisis and jobs growth.
"Mr Biden is fulfilling a key promise and upholding the longstanding principle that America’s national parks, monuments, and other protected areas are to be protected for all time and for all people," the White House said on Thursday.
The decisions effectively reverse moves made by former president Donald Trump, who allowed for mining and development in the national monuments — threatening to damage lands special to Native Americans and the natural beauty of ancient cliff dwellings and petroglyphs.
"National monuments and parks are part of our identity as our DNA," Mr Biden said.
The Bears Ears and Grand Staircase-Escalante monuments encompass more than 1.2 million hectares and were created by Democratic administrations under a century-old law that allows presidents to protect sites considered historically, geographically or culturally important.
The monuments cover vast expanses of southern Utah, where red rocks reveal petroglyphs and cliff dwellings and distinctive buttes bulge from a grassy valley.
Mr Trump invoked the century-old Antiquities Act to cut 800,000 hectares from the two monuments, calling restrictions on mining and other energy production a “massive land grab” that “should never have happened.”
His actions slashed Bears Ears, on lands considered sacred to Native American tribes, by 85 per cent, to just over 80,000 hectares. Grand Staircase-Escalante was cut by nearly half, leaving it at about 400,000 hectares.
"We have to come together and understand why this work is so critical," Mr Biden said.
"We're protecting and caring for forests, we're not just preserving the majesty of nature. We're safeguarding water sources ... not only saving birds and fish and the livelihoods of people who depend on them. We're also shoring up the natural defences to absorb the fury of hurricanes and superstorms."
The Northeast Canyons and Seamounts Marine National Monument is a large marine area in the Atlantic Ocean, southeast of Cape Cod.
It is also the only national marine monument in the Atlantic Ocean, as well as the first on the US East coast.
Mr Trump had made a rule change to allow commercial fishing in a nearly 13,000-square-kilometre area, an action that was praised by fishing groups but derided by environmentalists, who pushed Mr Biden and Interior Secretary Deb Haaland to restore protections.
Ms Haaland, the first Native American Cabinet secretary, travelled to Utah in April to visit the monuments, becoming the latest federal official to step into what has been a years-long public lands battle. She submitted her recommendations on the monuments in June.