By Aresu Eqbali
Clotilde Reiss, who turned 24 in her prison cell on July 31, was arrested on July 1 as she tried to fly out of Iran after a study trip.
She was wearing blue jeans, a dark coat and a colourful headscarf. A policewoman stood alongside.
"She is accused of collecting information and provoking rioters," the official IRNA news agency reported. It named the embassy employee only as Afshar.
A diplomatic source said it was "surprising to know Reiss was in the court."
"We came to know only this morning from television. We were not informed previously," he added.
Reiss was initially accused of spying because she had taken a photograph of an opposition demonstration in the central city of Isfahan and emailed it to a French friend in Tehran.
France's ambassador to Tehran, Bernard Poletti, has been allowed to see Reiss in the capital's notorious Evin prison just once since her arrest, but he has been allowed to talk to her twice by telephone.
On July 28, the French foreign minister said that in her latest telephone call Reiss told Poletti that "her morale and courage were holding up even if she remains worried about her future."
"We are continuing to demand that we be allowed to exercise our right to visit our countrywoman," ministry spokesman Frederic Desagneaux said at the time.
More than 10 other defendants detained during the wave of protests that followed Ahmadinejad's hotly disputed June 12 re-election were in the dock with Reiss.
It was the second hearing in their trial. A number of key reformist politicians and journalists are among them, the ISNA news agency said.
The new hearing had been due to be held on Thursday but was pushed back to Saturday as some defence lawyers asked for more time to study the charges against their clients.
Some 100 defendants were in the dock for the first hearing on August 1. They were charged with various offences, including rioting.
At that hearing, several of the accused withdrew earlier allegations of fraud in the presidential election, saying that Ahmadinejad's victory was clean.
Another 10 protesters were put in the dock in a separate trial on Sunday.
Ahmadinejad's main challenger Mir Hossein Mousavi and reformist former president Mohammad Khatami have both denounced the trials.
Ahmadinejad was sworn in on Wednesday for a second four-year term.
Prosecutor Abdolreza Mohabati said those in the dock on Saturday were accused of "designing a plan on behalf of the opposition and foreign countries to topple the regime by stealth."
Iranian officials have accused opposition leaders and their supporters of plotting a "velvet revolution."
