As a mass trial of reformist figures resumed in Iran on Saturday, a French researcher and an analyst at the British Embassy who have been accused of spying took the stand to apologize, saying they had only wanted to update their embassies on Iran’s recent political turmoil.

The two defendants were among more than 100 who have been accused of conspiring to topple the Iranian government in a so-called velvet revolution. The trial, which opened last Saturday, has included controversial confessions by prominent reformist figures, whose friends and relatives say they had been coerced through torture into denouncing the opposition movement.

The trial appears to be the latest effort by Iran’s hard-line establishment to intimidate and silence the opposition, which maintains that President Mahmoud Ahmadinejad’s landslide election on June 12 was rigged and that his presidency is not legitimate.

Prosecutors began Saturday by reading a long and wide-ranging list of accusations that seemed to implicate any Western organization with an interest in Iran — including media organizations, human rights groups and research institutes — in a vast, seditious plot. The defendants in court also included people the government said were members of a monarchist group and a terrorist group and who were accused of planning bombings. The French researcher, Clotilde Reiss, is a 24- year-old woman who was working at Isfahan University. She told the court that she had collected news and information about politics and the opposition protests that took place after the election, and presented some of it to officials at the French Embassy in Tehran.

“I realize this was a mistake,” she said, according to the semiofficial Fars news agency. “I apologize to the court and the people of Iran and I hope they will forgive me.”

Hussein Rossam, a political analyst at the British Embassy in Tehran who is an Iranian citizen, also took the stand after espionage charges were read against him. He said in detail that his job required him to gather information on Iranian politics and to convey that to his employers.

He then expressed “regret,” according to Fars, and asked for pardon and an opportunity to make up for any action that might have harmed the government. His lawyer then rose to say that Mr. Rossam’s activities were not spying, but the requirements of his job at the embassy.

Britain called the trial of its embassy employee an “outrage.”