Joe Biden restored environmental protections on Friday to three national monuments and their vast expanse of vital ecosystems and sacred Indigenous spaces, reversing cuts made by Donald Trump.

“These protections provide a bridge to our past, but they also build a bridge to a safer and more sustainable future,” said Biden. “One where we strengthen our economy and pass on a healthy planet to our children and our grandchildren.”

Biden signed three proclamations that increased the boundaries of Bears Ears to 1.36m acres, while restoring the Grand Staircase-Escalante to 1.87m acres – both spanning large swaths of southern Utah. He also reinstated protections for the Northeast Canyons and Seamounts Marine, about 130 miles off the coast of New England, and extended limits on commercial fishing.

The proclamations unraveled moves made by Trump, in which he slashed 85% of Bears Ears, leaving wide swaths of the site vulnerable to mining and other commercial activities. The Grand Staircase-Escalante was cut by about half. In 2020, Trump also stripped the environmental protections for the Northeast Canyons and Seamounts Marine, a marine monument home to more than 1,000 distinct species.

After years of fighting back against cuts to the national monuments, the announcement served as a key victory for environmental and Indigenous groups. Many expressed their relief and gratitude.

The interior secretary, Deb Haaland, the first Indigenous cabinet secretary, fought back tears as she applauded the administration’s actions for “bending the arc of the moral universe toward justice”.

“This is a place that must be protected in perpetuity for every American and every child of the world,” she said, referring to Bears Ears.

The monument, which was named for two striking buttes in south-eastern Utah, includes ancient cliff dwellings and sacred burial grounds. It is a place of worship and an important space for ceremonial activities, explained the Hopi Tribe vice-chairman, Clark Tenakhongva.

“It’s on the same level as any kind of church or foundation or facility,” said Tenakhongva, who is also co-chair for the Bears Ears Inter-Tribal Coalition. “It’s very important to the lifeline of all nations and all people.”

Staff attorney Matthew L Campbell for the Native American Rights Fund, which represents three of the tribes that have been involved in a years-long legal battle to protect Bears Ears, including the the Hopi Tribe, said he was very excited that this day had finally come.

“The tribes have fought long and hard to protect this area,” he said. “It’s a sacred place that is intricately tied to the tribes’ histories and who they are as a people and it certainly deserves the protections and we’re glad and happy to see that those protections are going to be restored.”

Shaun Chapoose, chairman of the Ute Indian Tribe business committee and a member of the Bears Ears Inter-Tribal Coalition, said in a statement: “President Biden did the right thing restoring the Bears Ears national monument. For us the monument never went away. We will always return to these lands to manage and care for our sacred sites, waters and medicines.”

Brad Sewell, senior director of the Natural Resources Defense Council’s oceans program, said he was thrilled with the decision and the fact that it will help to preserve important marine wildlife and the deep-sea coral gardens within the Northeast Canyons and Seamounts Marine national monument.

“We’re very happy for the country. This action will preserve an extraordinary place – our newest blue park for generations to come,” said Sewell.

But some Republican leaders have said they are disappointed with the decision and the “winner-take-all mentality” it represented.

In a statement released with other state leaders, Utah’s Republican governor, Spencer Cox, said: “The president’s decision to enlarge the monuments again is a tragic missed opportunity – it fails to provide certainty as well as the funding for law enforcement, research, and other protections which the monuments need and which only congressional action can offer.”

During Biden’s campaign for the presidency, he had pledged to restore these monuments’ boundaries. Just after his inauguration, he signed an executive order requiring the interior department to review the monuments, and make a decision about whether it would be appropriate to restore them.

Last spring, Haaland traveled to Utah to visit two of the monuments, and then later recommended Biden return them to their previous size and protections.