A German citizen serving a three-year prison sentence in Iran has been released as part of a prisoner swap, Iran's judiciary announced Tuesday.

The man was exchanged for Ahmad Khalil, an Iranian being held in Germany on suspicion of violating US sanctions, said Iran's judiciary spokesman Gholamhossein Esmaili. Khalil had been arrested on a request from Washington and was subject to extradition to the US.

"We insisted that first the Iranian citizen should return home ... then the German citizen was allowed to leave Iran on Monday," Esmaili told a press conference in Tehran.

"We announced that we are ready to (release) this German national... on condition that they (the Germans) do not extradite our citizen to America."

The German government did not immediately comment on the apparent prisoner swap. 

Read more: US scholar released in Iran, jailed Iranian scientist freed in prisoner swap

Khalil was allowed to fly home on Sunday with Iranian Foreign Minister Mohammad Javad Zarif, who had been attending a security conference in Munich.

Call for release of French citizens

Esmaili said the German man was "arrested (a) while ago and was sentenced to three years in jail for taking pictures from sensitive places."

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

Two French academics who have been held in Iran since June are due to face court next month, Esmaili said. France has demanded French-Iranian academic Fariba Adelkhah and her French colleague Roland Marchal be released, but Tehran has dismissed the call as foreign interference.

Read more: Iran executes 'defense contractor' over spying for the CIA

In December, Iranian authorities released Chinese-American Xiyue Wang, who was arrested in 2016 and charged with spying. In return, the US freed jailed Iranian scientist Massoud Soleimani.

Tensions between Tehran and Washington have spiraled since 2018, when US President Donald Trump pulled out of the 2015 Iran nuclear deal and reimposed a series of damaging sanctions on Iran.

nm/stb (AFP, Reuters)

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