ROME (AP) — Italy’s highest court has annulled an arrest warrant for a key suspect in the Vatican’s fraud and extortion trial, his lawyers said Wednesday, putting into question whether and when he might be extradited from Britain.

In a decision Tuesday, the Court of Cassation sent the case back to Rome’s Tribunal for Review, which in June upheld the arrest warrant for Gianluigi Torzi. A Cassation official said the court’s written ruling, explaining the reason for the annulment decision, would be released within a month.

Vatican prosecutors have accused Torzi of extorting 15 million euros ($17.8 million) from the Holy See to turn over ownership of a luxury London building in which the Vatican had invested some 350 million euros ($420 million), largely donations from the faithful. Torzi denies wrongdoing.

Italian prosecutors have also accused Torzi of related financial crimes and issued a warrant for his arrest in April. In confirming the Italian warrant, the Tribunal for Review strongly backed the Vatican thesis, saying the evidence showed Torzi used bad-faith negotiations, last-minute contractual changes and a web of accomplices to defraud the Holy See.

He was arrested in London based on the warrant but freed pending extradition proceedings. The Vatican doesn’t have an extradition treaty with Britain, so any extradition back to Rome would be dependent on the Italian investigation.

The Vatican trial against Torzi and nine other people began in July and recently resumed with the tribunal president ordering prosecutors to essentially redo their investigation in whole or in part because they made a series of procedural errors that had deprived the suspects of their defense rights.

Torzi’s lawyers, Ambra Giovene and Marco Franco, said the Court of Cassation ruling “will be an important step in proving the innocence of their client.” They noted that Italian prosecutors had based their investigation and arrest warrant request on evidence provided by the Vatican.