US court throws out plea deal for alleged mastermind of 9/11 attacks

The decision Friday undoes an attempt to wrap up more than two decades of military prosecution beset by legal and logistical troubles.

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

Mohammed is accused of developing and directing the plot to crash hijacked airliners into the World Trade Centre and the Pentagon. (AFP/File)

The decision Friday undoes an attempt to wrap up more than two decades of military prosecution beset by legal and logistical troubles. It suggests no quick end to the long struggle by the US military and successive administrations to bring to justice the man charged with planning one of the deadliest attacks ever on the United States.

Mohammed is accused of developing and directing the plot to crash hijacked airliners into the World Trade Centre and the Pentagon.