Frenchman held in Iran starts new hunger strike: sister
Briere, who was sentenced to eight years in jail for espionage, is one of seven French and more than two dozen foreign nationals who campaigners say Iran has jailed in a strategy of hostage-taking to extract concessions from the West.
Held in the prison of Vakilabad in the eastern city of Mashhad, he had already gone on hunger strike once before, at the end of December 2021.
"It's the only weapon he has," his sister Blandine Briere said in a statement.
He stopped eating on January 28, she said.
Philippe Valent, Briere's France-based lawyer, called the espionage charges against him "fiction" and his trial "a parody staged by the Revolutionary Guards", the branch of the Iranian security forces entrusted with the preservation of the regime.
Briere, the lawyer said, is "mentally and physically exhausted" in the "gloomy" prison which he said was known for frequent "extra-judicial executions" of inmates.
Majidreza Rahnavard, 23, the second of four people executed over the protests, was held in Mashhad and hanged in public in the city on December 12.
The conditions of Briere's incarceration were "exceptionally harsh", and he was being denied his rights, Valent said.
Iran needed to be held accountable for the danger to Briere's "physical and mental wellbeing", the lawyer said.
Another detainee in Iran, 64-year-old Franco-Irish citizen Bernard Phelan held since October 1, last month suspended a hunger strike that included refusing water, at the request of his family who feared for his life.
Phelan, a Paris-based travel consultant was arrested while travelling and is being held in Mashhad in northeastern Iran.
Iran accuses him of anti-government propaganda, a charge he has denied.