A French court on Wednesday approved the extradition of a suspect in an alleged bomb plot against an Iranian opposition rally to Belgium.
The plan to target a gathering of the National Council of Resistance of Iran in a Paris suburb came to light a few days after the June 30 event.
Six people were arrested in Belgium, France and Germany, two of whom were later released.
Belgian police believe the man arrested at a hotel in Paris, identified as Merhad A, aged 54, is an accomplice of a husband-and-wife team caught in Brussels in possession of 500 grams of an explosive and a detonator.
The couple were identified as Amir S, 38, and Nasimeh N, 33.
All three are Belgians of Iranian origin.
Separately, German police detained Assadollah Assadi, an Iranian diplomat based in Vienna.
German prosecutors suspect Mr Assadi, believed to be an intelligence agent, ordered the couple to attack the rally and gave them the explosive at a June meeting in Luxembourg.
Iran has dismissed the alleged bomb plot as a "sinister false flag ploy" designed to discredit it as it faces diplomatic tensions with the United States.
The rally in the Paris suburb of Villepinte was attended by several allies of US President Donald Trump, including former New York mayor Rudy Giuliani and former House speaker Newt Gingrich, both of whom urged regime change in Iran.
Belgian authorities requested the extradition of both Mr Assadi and Merhad A.
Merhad A was questioned by French police for three days before being taken into custody. He has agreed to he handed over to Belgium.
He was arrested by police acting on a tip-off. In his phone, he had an Austrian Sim card with one number on it.