Iran has exchanged a jailed British-Australian academic, Kylie Moore-Gilbert, with three Iranians who had been detained abroad, Iran's state broadcaster IRIB reported on Wednesday.
Moore-Gilbert, a specialist in Middle East politics at the University of Melbourne, was detained in Iran in September, 2018 and had been serving a 10-year sentence for espionage.
State TV said that an Iranian businessman and two Iranian citizens who had been held abroad "on baseless charges" had been exchanged for Moore-Gilbert.
It gave no further details about the three Iranians, but said they were detained for trying to circumvent US sanctions, reimposed on Iran in 2018 when Washington exited Iran's nuclear deal with six powers.
Footage aired by state TV showed Moore-Gilbert at the airport with a headscarf, appearing to be waiting to board a plane to leave Iran.
The footage also showed three men wearing face-masks with Iranian national flags on their shoulders and one in a wheelchair with his both legs amputated at the knee, were welcomed at the airport by Iranian officials with chants of "Allahu akbar" (God is Greatest).
There was no immediate comment from Britain's Foreign Office.
Iran's elite Revolutionary Guards have arrested dozens of dual nationals in recent years, mostly on espionage charges.
Rights activists have accused Iran of arresting dual nationals to try to win concessions from other countries. Tehran denies it holds people for political reasons and has accused many of the foreigners in its jails of espionage.