Trump met with Zinke on Friday, primarily to discuss the "monuments report that will be coming out shortly," according to White House press secretary Sarah Sanders.
Earlier this year Trump initiated a review -- led by Zinke -- of more than two dozen national monuments designated by Presidents Bill Clinton, George W. Bush and Barack Obama.
If the President officially announces the plan to shrink either national monument it would make Trump the first president to shrink a national monument using the Antiquities Act.
"I'm approving the Bears Ears and Grand Staircase recommendation for you, Orrin," Trump told Hatch in a phone call Friday morning, the spokesperson said.
In response, Hatch said he was "incredibly grateful the President called this morning to let us know that he is approving Secretary Zinke's recommendation on Bears Ears."
"We believe in the importance of protecting these sacred antiquities, but Secretary Zinke and the Trump administration rolled up their sleeves to dig in, talk to locals, talk to local tribes and find a better way to do it," Hatch said. "We'll continue to work closely with them moving forward to ensure Utahns have a voice."
Bears Ears, a 1.3-million-acre parcel of lands that includes world-class rock climbing, age-old cliff dwellings and land sacred to Pueblo Indians, was first designated a national monument by Obama in 2016.
The former president used the Antiques Act -- a presidential power that was first signed by President Teddy Roosevelt in 1906 -- to protect large swaths of land during his presidency, making him the president who protected more federal land than any of his predecessors.
Zinke released an interim report earlier this year that recommended shrinking the size of Bears Ears after local officials and Utah Republicans protested the Obama-era designation but stopped short of suggesting the elimination of any federal designations.
"The Bears Ears National Monument contains some objects that are appropriate for protection under the act," Zinke wrote in his report, referencing rock art and Native American ceremonial sites and dwellings. "However, having conducted the review ... I find that the Bear Ears National Monument does not fully conform with the policies set forth" in Trump's executive order."
The decision over Bears Ears has pinned these local officials against environmental and outdoor advocacy groups, many of whom have spent considerable money to protect the national monument.
These groups have also said they plan to sue the federal government if Trump decides to accept Zinke's suggestion and shrink the park.
"President Trump is making it clear that he stands with the most partisan and anti-lands faction of his party, not the majority of Americans," Jamie Williams, president of the Wilderness Society, said in a statement. "The sneaky closed-door meetings that continue to happen are a slap in the face to the very public process that drove the protection efforts for Bears Ears as well as other national monuments across our country."
Phil Lyman, a San Juan County, Utah, commissioner, told CNN on Friday that they had been informed the President intends to shrink the size of Bears Ears.
Though Sanders would not confirm Trump's plan, she said that Trump did plan to visit Utah "in the first part of early December" when asked about Bears Ears.
The decision to shrink the national monuments would go against some of what Trump said on the campaign trail, when he told supporters that he was in favor of federal control of public lands. As President, though, Trump has recently fallen more in line with Republican orthodoxy on the issue and said he wants to give more control to the states.