The Biden administration has doubled down on its unusual court battle to derail a plea deal that the government itself had reached with accused 9/11 mastermind Khalid Sheikh Mohammed.

It's the latest development in the U.S. military's struggle to bring to justice the man charged with planning the Sept. 11 attacks on the United States.

The move comes after years of legal battles over the case, which remains in pretrial hearings 17 years after charges were first filed.

The Biden administration asked a federal appeals court on Tuesday to block a plea agreement for accused 9/11 mastermind Khalid Sheikh Mohammed that would spare him the risk of the death penalty in one of the deadliest attacks ever on the United States.

Defense Secretary Lloyd Austin cannot nix the controversial plea deals struck with alleged 9/11 mastermind Khalid Sheikh Mohammed and two other Guantanamo Bay detainees, according to a Monday military appeals court decision.

The Biden administration is asking for a federal appeals court to temporarily block a plea deal agreement with three detainees in Guantanamo Bay, Cuba.

The Pentagon has asked a federal court to stay a plea deal for alleged 9/11 mastermind Khalid Sheikh Mohammed, who is slated to plead guilty on Friday.

The Justice Department, on behalf of the Pentagon, on Tuesday asked an appeals court to block an effort to enforce plea deals reached with four accused conspirators of the Sept. 11, 2001, terrorist attacks.