By Christine Hauser • New York Times News Service

Patagonia, REI and other outdoor clothing and equipment retailers are speaking out against President Donald Trump’s plan to slash the size of two national monuments in Utah by some 2 million acres.

Trump on Monday announced that his administration would shrink Bears Ears National Monument, a region of red rock canyons, by 85 percent, and cut another monument, Grand Staircase-Escalante, to about half its current size.

“The president stole your land,” Patagonia said in a pop-up message on its website. “In an illegal move, the president just reduced the size of Bears Ears and Grand Staircase-Escalante National Monuments. This is the largest elimination of protected land in American history.”

REI said it would continue to pursue bipartisan support to protect public lands and “prevent death by a thousand cuts.”

“We just lost millions of acres of protected land,” the company said. “But we remain united as a community.”

North Face, citing federal lawsuits that were filed in anticipation of Trump’s decision, said it was donating $100,000 to an education center for Bears Ears.

And the Canadian company Arc’teryx announced it would donate the net proceeds of its Nov. 28 post-Thanksgiving eCommerce sales in the United States to The Conservation Alliance and an additional $30,000 to the alliance’s Public Lands Defense Fund, which is challenging the legality of Trump’s move.

Trump announced his decision to reduce the public lands during a speech at Utah’s State Capitol in Salt Lake City. President Barack Obama made Bears Ears a monument in 2016, and President Bill Clinton classified Grand Staircase-Escalante in 1996, using the Antiquities Act, which allows presidents to set aside landmarks and “other objects of historic or scientific interest.”

At least one lawsuit has already been filed, in District Court in Washington, D.C., on Monday — by the Wilderness Society, Great Old Broads for Wilderness and eight other groups — in defense of Grand Staircase. It named Trump, Interior Secretary Ryan Zinke and Brian Steed, of the Bureau of Land Management, as defendants, saying Trump exceeded his authority under the Constitution and the Antiquities Act that established the monuments.

The expected legal battle could alter the course of U.S. land conservation and usher in logging, mining and other commercial activities onto preserved public areas.