Clotilde Reiss, a 24-year-old who was arrested on July 1 and charged with acting against Iran's national security, is to hear the verdict in Tehran on Saturday, a Tehran prosecutor said.
"We expect that her innocence will be recognized by Iranian justice and we want Clotilde Reiss to return to France as soon as possible," said foreign ministry spokesman Bernard Valero.
"I have one certainty, which is that our compatriot is innocent," he added.
Reiss is accused of supporting opposition protests that erupted after President Mahmoud Ahmadinejad was re-elected in June.
She was arrested shortly before she was to fly home after a six-month study and teaching assignment. In the closing weeks of her stay she witnessed the protests, took pictures and emailed them to friends.
The young Iran expert's lawyer Mohammad-Ali Mahdavi Sabet said this week he hoped the court hearing on Saturday will be her last.
The arrest of Reiss has stoked tensions between France and Iran, which already are at odds over Tehran's nuclear programme and Paris's harsh criticism of the regime's crackdown on opposition protesters.
