The Biden administration on Tuesday suspended oil leases in the Arctic National Wildlife Refuge in Alaska, blocking plans for the first-ever drilling program in the pristine 19-million-acre wilderness.

The Interior Department said the program will be on hold until it completes a comprehensive analysis under the National Environmental Policy Act. The review could ultimately lead to the leases being voided altogether, the department said.

“Today marks an important step forward fulfilling President Biden’s promise to protect the Arctic National Wildlife Refuge,” Gina McCarthy, the White House national climate adviser, said in a statement. Drilling could change “the character of this special place forever,” she added.

The decision is the latest twist in more than 30 years of fights, often highly partisan, over how to manage what many consider some of the country’s last unspoiled wilderness.

Republicans and oil interests are still adamantly pushing for industry’s right to explore this remote northeast corner of Alaska. Even so, it comes at a time when the industry’s interest in working there has waned significantly.