President Joe Biden on Tuesday is set to designate two new monuments and, in doing so, establish the largest tract of protected land in the continental United States by expanding a corridor out West, the White House said.

But his planned remarks from Thermal, California, on Tuesday afternoon announcing the designation of the two new monuments were scrapped because of “weather issues,” according to the White House, amid a “life-threatening” windstorm in California with fire risks. They are being rescheduled for next week at the White House.

The proclamations Biden plans to sign would create the Chuckwalla and Sáttítla Highlands National Monuments, with the first in southern California and the latter in the northern mountainous part of the state.

The two new monuments total nearly 850,000 acres, according to the administration.

The Chuckwalla National Monument, which will be situated south of Joshua Tree National Park, creates the new Moab to Mojave Conservation Corridor, a nearly 18 million acre tract of protected land spanning about 600 miles from southern California to Utah — the largest in the lower 48 states, according to the White House.

The Chuckwalla will protect 624,000 acres of land, “preserving critical habitat for imperiled and rare species, and ensuring the ancestral homelands and sacred cultural legacies of the region’s Tribal Nations endure,” the White House said.

The monument will protect the ancestral homelands of the Cahuilla, Chemehuevi, Mojave, Quechan and Serrano Nations.

The monument’s habitat includes 50 rare plant and animal species, the White House notes, including the desert bighorn sheep and its namesake, the Chuckwalla lizard.

The Sáttítla Highlands National Monument, meanwhile, will protect 224,000 acres, which will include parts of the Modoc, Shasta-Trinity and Klamath National Forests, the White House said, and will also include the dormant Medicine Lake Volcano, with an expanse 10 times larger than Washington’s Mount. St. Helens.

The land protected by this monument is also home to rare and vulnerable plants and animals, including the Cascades frog, the long-toed salamander, and the northern spotted owl.

The Departments of Interior and Agriculture said Biden used his authority under the Antiquities Act to designate these monuments monument.

Trump, in 2017, denounced prior uses of the 1906 law to protect land and drastically reduced the size of several national monuments during his first term.

The White House said Biden’s new designations serve as “a capstone to four years of historic conservation progress.”

The move comes a day after Biden issued a sweeping ban on all future oil and natural gas drilling on 625 million acres off of the U.S.’s coasts, including the entire East Coast, the eastern Gulf of Mexico, the Pacific off the coasts of Washington, Oregon and California, and portions of the Northern Bering Sea in Alaska.