Iranian authorities released French researcher Roland Marchal on Saturday, a French presidency official announced.

Marchal has been in prison since June 2019 when he was charged with "collusion against national security."

Read more: German citizen freed in prisoner swap, says Iran

Marchal, who is a senior researcher at the Paris Institute of Political Studies (Sciences Po), is set to arrive in France around midday on Saturday, the official confirmed.

French President Emmanuel Macron also urged Tehran to release Marchal's Franco-Iranian colleague Fariba Adelkhah, who remains in jail. Marchal went to Iran to visit Adelkah and the pair were subsequently detained after accusations of espionage.

Prisoner exchange

The academic's release came about after Iran and France agreed to swap Marchal and an Iranian detained by Paris over alleged violations of US sanctions against Tehran.

France therefore released engineer Jalal Ruhollahnejad, according to Iranian state broadcaster IRIB on Friday.

Dozens of foreigners and dual citizens have been detained by Iran's Revolutionary Guards — most of them on charges of espionage.

Last month, France demanded Adelkhah and Marchal be released, but Tehran had dismissed the call as foreign interference.

jsi/kl (AFP, Reuters)

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