WASHINGTON — The Trump administration on Thursday finalized plans to allow mining and energy drilling on nearly a million acres of land in southern Utah that had once been protected as part of a major national monument.

The Interior Department’s release of a formal land-use blueprint for the approximately 861,974 acres of land will allow oil, gas and coal companies to complete the legal process for leasing mines and wells on land that had once been part of Utah’s Grand Staircase-Escalante National Monument, established by President Bill Clinton.

In December 2017, President Trump cut the monument’s acreage about in half, aiming to open the newly unprotected land for drilling and development. At the same time, he removed about a million acres from another Utah monument, Bears Ears. Together, the moves were the largest rollback of public lands protection in United States history.