The Supreme Court has ruled against the Navajo Nation for a second time in its battle with the federal government over whether the tribe should have gotten more money for coal on its land.

The high court, in an unanimous opinion Monday, reversed a decision by the U.S. Court of Appeals for the Federal Circuit, ending the tribe's fight with the government.

"Today we hold, once again, that the tribe's claim for compensation fails," said Justice Antonin Scalia, writing for the court. "This matter should now be regarded as closed."

The sprawling Navajo reservation, which is the nation's largest, covers part of New Mexico, Arizona and Utah. The Peabody Coal Co. has mined coal on tribal lands for decades, paying the tribe taxes and mineral royalties.

In 1985, the tribe alleged that Peabody conspired with then-Interior Secretary Donald Hodel to persuade the tribe to accept a lower royalty than other government officials believed the tribe should be paid.