A divided federal appeals court has thrown out an agreement that would've allowed accused Sept. 11 mastermind Khalid Sheikh Mohammed to plead guilty in a deal sparing him the risk of execution for al-Qaida’s 2001 attacks.

The court found that Defense Secretary Lloyd J. Austin III had the authority to invalidate a contract reached between the accused mastermind and a Pentagon official.

A U.S. appeals court on Friday refused to allow Khalid Sheikh Mohammed, the accused mastermind of the September 11, 2001, attacks, and two of his co-defendants to plead guilty under agreements that would have spared them the death penalty.