Washington, D.C. ? A federal judge on Wednesday ruled that the Interior Department has “unreasonably delayed” its accounting for billions of dollars owed to American Indian landholders.

The federal agency “has not, and cannot, remedy the breach” of its responsibilities to account for the American Indian money, U.S. District Judge James Robertson said in a 165-page decision in a long-running federal lawsuit alleging mismanagement of American Indian trust funds.

“Indeed, it is now clear that completion of the required accounting is an impossible task” for the department, Robertson said, adding that he would schedule a hearing next month to discuss ways to solve the problem. He added that his conclusion that Interior is unable to perform an adequate accounting does not mean that the task is hopeless.

“It does mean that a remedy must be found for the department’s unrepaired, and irreparable, breach of its fiduciary duty over the last century. And it does mean that the time has come to bring this suit to a close,” he said.

The suit, first filed in 1996 by Blackfeet Indian Elouise Cobell, claims the government has mismanaged more than $100 billion in oil, gas, timber and other royalties held in trust from American Indian lands dating back to 1887.