A German court has agreed to allow a new prosecution witness in the trial of an 11 September suspect which appeared to have all but crumbled last month.
Mr Mzoudi admits knowing the hijackers but not their plans
The dramatic move has delayed the verdict in the case of Abdelghani Mzoudi which was expected this week.
Mr Mzoudi, 31, is accused of being an accessory to the murder of more than 3,000 in the 2001 attacks on America and membership of a terrorist group.
The Moroccan national was freed after new evidence cast doubt over the case.
A defence lawyer said the prosecution had applied to delay proceedings by 30 days to allow them to present new evidence.
No new date was given for the verdict, which had been expected on Thursday.
Prosecutors gave no details of the new witness but Mr Mzoudi's defence lawyer, Guel Pinar, said the witness was an unidentified Iranian intelligence officer who was claiming to have informed US authorities of an impending attack before September 2001.
The agent, according to Mr Mzoudi's lawyer, had also told German investigators that Osama Bin Laden's al-Qaeda network had threatened Mr Mzoudi's life because it believed he had co-operated with German authorities when questioned.
Ulrich von Jeinsen, a lawyer for American relatives of victims of the attacks who are co-plaintiffs in the case, said the
witness alleges that Mr Mzoudi was a key logistics chief in the plot.
He said the witness's evidence was "sensational" and the trial was "a whole new ball game".
Prosecutors say Mr Mzoudi helped the cell responsible for the attacks and want him to be given the maximum sentence of 15 years in jail.
New evidence that led to Mr Mzoudi being released by the court in December came in the form of a statement from an unidentified informant saying that there were only four people in the Hamburg cell responsible for the attacks - three pilots and Ramzi Binalshibh who is already in US detention.
The source was not named but the court said it believed it was Mr Binalshibh.
Mr Mzoudi is the second person anywhere in the world to be tried over the attacks.
Moroccan Mounir al-Motassadek was jailed in Germany in February as an accessory to more than 3,000 murders in New York and Washington as a result of 11 September.
The court which convicted Motassadek heard that he was a member of the Hamburg cell which planned the terror attacks.
He was jailed for 15 years.