Moussaoui charges may be dropped in bid for new trial

Desperate to secure a conviction in the so-called war against terror, the Bush administration is undertaking a high-risk legal manoeuvre in its prosecution of Zacarias Moussaoui, the only person charged in connection with the attacks of 11 September.

In a motion placed before a federal court in Alexandria, Virginia, prosecutors urged US District Judge Leonie Brinkema to throw out the charges against Mr Moussaoui, the suspected "20th hijacker". They hope that another court will then allow them to proceed with a fresh prosecution.

Mr Moussaoui's lawyers agreed that a dismissal was the only appropriate action, since the Bush administration has defied a court ruling to allow the defendant to call as witnesses three alleged senior al-Qa'ida members.

The al-Qa'ida suspects, currently in US custody, are Khalid Sheikh Mohammed, said to have been the mastermind behind the 11 September attacks; Ramzi Binalshibh, an alleged senior operational planner; and Mustafa Ahmed al-Hawsawi, accused of being an al-Qa'ida paymaster. Defence lawyers have said the three could clear their client of any involvement in the attacks.

The Bush administration has argued that such a move would be harmful to national security. In a statement, the Justice Department said: "We believe the Constitution does not require, and national security will not permit, the government to allow Moussaoui, an avowed terrorist, to have direct access to his terrorist confederates who have been detained abroad as enemy combatants in the midst of a war."

While Judge Brinkema has little alternative but to dismiss the charges - which she is likely to do early next week - the Bush administration has no intention of allowing Mr Moussaoui, a French citizen, to escape prosecution.

If the charges are dismissed, the prosecution believes it could place the case before the 4th US Circuit Court of Appeals in Richmond, which has already heard oral arguments in the government's appeal against the order granting Mr Moussaoui the right to question the captives. The panel of judges has said it will rule only after Judge Brinkema has dealt with the government for defying her order.

The prosecution is relying on the fact that the 4th Circuit Court is known as the most conservative court in the nation and has previously displayed sympathy with requests from the government concerning issues of national security above claims of due process from defendants.

A refusal by the 4th Circuit Court would be a symbolic and embarrassing slap to the Bush administration. In such circumstances it has made clear that Mr Moussaoui would almost certainly be placed before a military tribunal and tried as an enemy combatant.