Benjamin Briere has been charged with espionage and propaganda against Iran after being arrested in May 2020.
France has slammed an eight year jail sentence on spying charges handed by an Iranian court to French citizen Benjamin Briere.
"This verdict, which nothing can justify, is unacceptable," the Foreign Ministry said in a statement on Tuesday, adding that Briere had been arrested "while travelling as a tourist" in Iran.
Briere, 36, was also given an additional eight-month sentence for propaganda against Iran's religious system, his lawyer Philippe Valent said in a statement.
"This verdict is the result of a purely political process that is ... devoid of any basis," he said.
Slamming the trial, which began on Thursday, as a "masquerade", he added that Briere "did not have a fair trial in front of impartial judges."
He had not been allowed to access the full indictment against him, Valent added.
Iran's judiciary was not immediately available for comment.
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'Using him as currency'
One of his Iranian lawyers Saeid Dehghan told Reuters news Briere is in state of shock, adding that they would appeal against the verdict within 20 days.
Briere, who is currently on hunger strike, has been held since May 2020.
He was arrested after flying a helicam — a remote-controlled mini helicopter used to obtain aerial or motion images — in the desert near the Turkmenistan-Iran border.
Briere is one of more than a dozen Western citizens held in Iran, described as hostages by activists who say they are innocent of any crime and detained at the behest of the powerful Revolutionary Guard to extract concessions from the West.
Nationals of all three European powers involved in the talks on the Iranian nuclear programme — Britain, France and Germany — are among the foreigners being held.
"It is not tolerable that Benjamin Briere is being held a hostage to negotiations by a regime which keeps a French citizen arbitrarily detained merely to use him as currency in an exchange," Valent added.
He said Briere was "more and more weakened" by a hunger strike that has now lasted a month.
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