WASHINGTON, Dec 29 (Reuters) - Lawyers for former Iraqi president Saddam Hussein, who could be hanged within hours, on Friday asked a U.S. court to order a halt to his execution. In a last-minute filing to the U.S. District Court of Washington, Hussein's lawyers asked for a temporary stay of execution because Saddam is a defendant in a civil case in the same court and he has been prevented from being able to defend himself. U.S. officials have denied a remark by a lawyer for Saddam that their forces have already handed him over to Iraqi custody for execution.