When President Trump sharply reduced the size of Bears Ears National Monument in Utah by more than 1.2 million acres, he claimed it was necessary because recreation was virtually impossible within the site’s boundaries.

“You can’t go hunting, you can’t go fishing, you can’t do anything, you can virtually not even walk on it,” Mr. Trump said during a ceremony in the Oval Office last month.

The No. 2 official at the Interior Department, Kate MacGregor, chimed in to agree with the president, saying, “That’s exactly right, sir, so you are remedying that today.”

But recreation has been allowed in Bears Ears since President Barack Obama designated the monument in 2016. And government documents reviewed by The New York Times show that Trump administration officials were briefed on recreational opportunities inside the monument about a month before the Oval Office event.

Utah officials, who pushed for shrinking the monument, told the Trump administration in June that there was “current recreational access” to Bears Ears, according to the documents, which The Times obtained via a public records request.

The state officials specifically cited two trails popular among hikers, backpackers and off-road vehicle drivers, the documents show. (Other trails attract scores of horseback riders, mountain bikers and rock climbers, as Mr. Obama noted when he designated the monument.)

The documents suggest that the administration was “lying or spreading misinformation about these fantastic public lands” when it justified cutting the protected areas, said Steve Bloch, the legal director at the nonprofit Southern Utah Wilderness Alliance, who reviewed the records at the request of The Times.

National monuments are public lands that are legally protected from oil and gas drilling, mining and other industrial development. They have similar protections as national parks, but while national parks are created by Congress, national monuments can be created by presidents through the Antiquities Act of 1906.

Taylor Rogers, a White House spokeswoman, did not answer questions about the documents but said in an email that “the Obama and Biden administrations abused the Antiquities Act to lock up millions of acres of Utah’s public lands, impoverishing local communities and sharply restricting access for recreation, grazing, resource development and fire prevention.”

Charlotte Taylor, a spokeswoman for the Interior Department, also did not address the documents but said in an email that previous administrations “shut hunters, anglers and other sportsmen out of land they had accessed for generations.”

Mr. Trump signed executive orders last month to cut Bears Ears and a second national monument in Utah, Grand Staircase-Escalante, by more than 90 percent. Both sites are known for their sandstone canyons and vast mesas, which are rich in wildlife habitat as well as archaeological sites of importance to Native American tribes.

During his first term, Mr. Trump shrank Bears Ears by 85 percent and cut Grand Staircase nearly in half. But tribes and environmentalists sued over the move, saying the Antiquities Act authorized presidents to designate monuments but not to abolish or shrink them. President Joseph R. Biden Jr. subsequently restored sweeping protections to both sites before a court could issue a final decision. Mr. Trump’s new second-term cuts are even bigger.

The documents reviewed by The Times show that Redge Johnson, the director of Utah’s Public Lands Policy Coordinating Office, sent a memo in June to Sam Crofts, a senior adviser at the Interior Department, detailing Bears Ears’ history, geology and recreational opportunities.

The memo said that a route called the Peavine Corridor was open to off-road vehicles and provided “motorized access deep into the area.” It added that “backpackers often use Rig Canyon as a junction point on massive wilderness loops,” including a popular 40-mile loop.

Mr. Crofts, a former policy director for Senator Mike Lee, Republican of Utah, did not respond to a request for comment. Representatives for Utah’s Public Lands Policy Coordinating Office also did not return a request for comment.

Bears Ears is the ancestral homeland of five tribes in the region: the Navajo Nation, Hopi Tribe, Ute Indian Tribe, Ute Mountain Ute Tribe and Pueblo of Zuni. It contains thousands of archaeological sites that tribes consider culturally significant, including the remains of burial grounds, cliff dwellings and rock art panels.

The monument also boasts “world class outdoor recreation opportunities,” Mr. Obama wrote in his proclamation designating Bears Ears, which cited “rock climbing, hunting, hiking, backpacking, canyoneering, whitewater rafting, mountain biking and horseback riding.”

Louis Williams, the founder and owner of Ancient Wayves River and Hiking Adventures, which provides tours of Bears Ears led by Indigenous guides, said he watched live as Mr. Trump signed the executive order to shrink the monument.

“I was shaking my head,” Mr. Williams said. “I was like, ‘I wonder if he’s ever been here to this region, because if he knew this region, he would find out this place is totally accessible.’”

But Ben Burr, the executive director of the BlueRibbon Coalition, a group that pushes to open public lands to off-road vehicles, said he supported Mr. Trump’s move. He noted that the Biden administration proposed a plan to prohibit off-road vehicles across 600,000 acres of the monument, though it never took effect.

“Nobody ever felt those restrictions because the plan was adopted in the final midnight hours of the Biden administration, and then it was never actually enforced,” Mr. Burr said. “So we think that the discussion around what was allowed and not allowed in these monuments has been kind of obfuscated by that.”

The documents did not mention hunting or fishing. But the Utah Department of Natural Resources, which houses the Public Lands Policy Coordinating Office, allows people to hunt and fish in Bears Ears if they have valid licenses and tags.