TEHRAN - Iran confirmed Tuesday the arrest of a French-Iranian academic without giving any details of her case, the latest in a long list of dual nationals held in the country's prisons.
The detention of Fariba Adelkhah, 60, risks increasing tension between Paris and Tehran at a critical moment in efforts to save a landmark 2015 nuclear deal.
Adelkhah is a well-known expert on Iran and Shiite Islam at France's prestigious Sciences Po university.
"She is among suspects that have been recently arrested," Iran's judiciary spokesman Gholamhossein Esmaili said, without specifying the accusations against her.
"Now is not an appropriate time to give more information on this case," Esmaili told reporters at a news conference broadcast by the judiciary's news website Mizan Online.
Sciences Po said the arrest of the researcher was "unacceptable and shocking".
"We will do our utmost to ensure our colleague Fariba is released as soon as possible and under the best conditions," it said in a statement.
French President Emmanuel Macron expressed concern for her welfare on Monday after his government said the dual national was arrested but had been denied contact with consular staff.
"What has happened worries me a great deal," Macron said. "We have been aware of this for some days."
"I have expressed my disagreement and asked President (Hassan) Rouhani for clarification," he said, adding that France had so far received no meaningful explanation.
'Unacceptable and shocking'
Asked about French requests for access, Iran's judiciary spokesman said a decision about how to respond would be taken at "an appropriate time".
Adelkhah is the latest Iranian national with a Western passport to be arrested in Iran.
Nazanin Zaghari-Ratcliffe, a British-Iranian project manager with Thomson Reuters Foundation, has been detained in Tehran since 2016 on sedition charges, a case that has caused major tensions with the United Kingdom.
Other Iranian dual nationals jailed in Iran include Iranian-American Siamak Namazi and his father Baquer, who are serving 10-year sentences for espionage in a case that has outraged Washington.
Chinese-American Xiyue Wang, a Princeton University researcher, is serving a 10-year sentence for espionage, and US national Michael White, 46, was this year also sentenced to 10 years.
Adelkhah's arrest comes as Macron seeks to lead European efforts to find a way of keeping alive the 2015 nuclear deal that limits Iran's atomic programme.
Macron has sent an envoy to Tehran twice in the past month and was even rumoured to be considering becoming the first French president in more than 40 years to travel to the Iranian capital.
Not 'physically strong'
The hard-won nuclear deal is at risk of collapsing after President Donald Trump pulled the US out unilaterally, leading Iran in recent weeks to violate safeguards that limited its stockpiling and enrichment of uranium.
Jean-Francois Bayart, a French academic and friend of Adelkhah's, said he and colleagues had alerted French authorities when the anthropologist did not return home from a trip to her homeland as scheduled on June 25.
"She has been visited by her family. She hasn't been mistreated, but I'm worried about her because she isn't physically strong," Bayart said.
"We don't know how long this totally unacceptable detention is going to last."
"Iran doesn't recognise dual nationality, so for them she is Iranian, which is why consular access has not been permitted," he added. "But talks have taken place at the highest levels between the countries."
Bayart said Adelkhah had arrived in France in 1977 to study.
French academic Clotilde Reiss was detained in Iran for 10 months in 2009-10 before being released in a case that attracted widespread attention at the time.
At around the same time as her release, French judicial authorities freed Ali Vakili Rad, who had been convicted of the 1991 murder outside Paris of the ousted shah's former prime minister Shapour Bakhtiar.
Bakhtiar's murder happened during a thaw in relations between France and Iran when a state visit to Tehran by then President Francois Mitterrand, which would have been a first after the 1979 Islamic Revolution, was being mulled.