President Donald Trump on Monday reduced the size of two national monuments in Utah, undoing protections established by former presidents on public lands that are sacred among many Native Americans.

Bears Ears and Grand Staircase-Escalante national monuments in southern Utah have ancient cliff dwellings, petroglyphs and scenic canyons, as well as coal and uranium deposits that state officials want made available for development.

Trump, a Republican, issued proclamations under the Antiquities Act to reduce their size. He took similar actions during his first term, but those were reversed by President Joe Biden, a Democrat.

The latest move comes as Trump and other Republicans have drastically reshaped the management of vast taxpayer-owned lands concentrated in Western states. Trump administration officials and congressional Republicans have sought to expand drilling, mining and logging on public lands, while removing protections for imperiled species and rolling back rules for conservation.

President Bill Clinton, a Democrat, established Grand Staircase-Escalante National Monument in 1996, and President Barack Obama, also a Democrat, created Bears Ears National Monument in 2016 under the Antiquities Act. The 1906 law gives presidents the powers to protect sites considered historic, archaeologically significant or culturally important.

Davina Smith-Idjesa, a citizen of the Navajo Nation and co-chair of the Bears Ears Inter-Tribal Coalition, said tribal leaders had braced for a reduction since Trump was elected to a second term. She said Monday it was “heartbreaking” and accused federal officials of sidestepping their legal responsibility to consult with tribal nations that would be impacted.

“From a Navajo perspective, Bears Ears is not simply a piece of federal public land,” Smith-Idjesa said. “This is a living cultural site that holds our histories, our ceremonies, our traditional foods and medicines and our ancestors’ footprints.”

Utah officials have long fought against the monument designation and have argued that the state should be in charge of controlling its own lands. Trump in his first term reduced their size, calling their creation a “massive land grab.” Combined they span more than 3.2 million acres (13 million hectares), an area nearly the size of Connecticut.

“This is a big day for Utah,” Utah Gov. Spencer Cox said at a White House signing ceremony with Trump. “These monument designations are supposed to be the smallest area as possible to protect the antiquities.”

Bears Ears was the first national monument protected at the request of tribal nations that consider the land sacred. The landscape contains ancestral villages, ceremonial and burial sites and features in some tribes’ creation and migration stories. Its designation honored five tribes in the region — Navajo, Hopi, Zuni, Ute Mountain Ute and Uintah-Ouray Ute.

Home to hundreds of thousands of objects of cultural and scientific significance, Bears Ears is jointly managed by an agreement between tribal nations and federal agencies.

Grand Staircase-Escalante consists of cliffs, canyons, natural arches and archaeological sites, including rock paintings. It holds large coal reserves, while the Bears Ears area has uranium.

The national monument designation provides sweeping protections not just for significant geological features or artifacts but also for the surrounding landscape, banning drilling, mining and new construction nearby. Proponents of Trump’s plan to downsize say the protective boundaries stretch too far and hinder mining for critical minerals.

Biden designated or expanded more than a dozen monuments and had a goal to conserve at least 30% of U.S. lands and waters by 2030.

Trump’s policies are largely the opposite: He wants to tap into the natural resource wealth of federal lands that total more than 100,000 square miles (260,000 square kilometers) and offshore areas under federal control, such as in the Gulf of Mexico and off Alaska.

That’s drawn a sharp backlash from Democrats and conservationists, who warn of the wholesale disposal of treasured landscapes for commercial gain.

Trump Interior Secretary Doug Burgum had said last year that federal officials would review and consider redrawing the boundaries of national monuments as part of a push to expand U.S. energy production.

Trump’s in his current term has used proclamations to lift commercial fishing prohibitions within expansive marine monuments in areas of the Pacific Ocean and in the Atlantic Ocean off the New England coast. Those monuments were created by Democratic and Republican administrations. The effort to boost the fishing industry, which has been challenged in court, marks a dramatic shift in federal policy by prioritizing commercial interests over efforts to allow the fish supply to increase.

The Supreme Court has affirmed the president’s authority to create national monuments, and both Democrats and Republicans have used the Antiquities Act. But there’s been debate about whether Trump has the authority to change the boundaries of existing monuments.

Some Republicans have tried to sell or transfer federal lands to states or other entities. Those efforts have largely fallen flat: A push by some GOP lawmakers in the House to sell public lands ran into bipartisan opposition, while another proposal by Sen. Mike Lee of Utah to sell more than 3,200 square miles (8,300 square kilometers) of federal lands was removed from Republicans’ big tax and spending bill.

The U.S. Supreme Court last year turned back a lawsuit from Utah officials who sought to wrest control of vast areas of public land within the state from the federal government.