Ali Vakili Rad (centre) stabbed and strangled Shapour Bakhtiar
An Iranian convicted of the 1991 murder of Iranian former Prime Minister Shapour Bakhtiar has been released from prison in France.
Ali Vakili Rad, who faced a deportation order, boarded a flight from Orly airport to Tehran soon after leaving his prison in Poissy under escort.
Iran recently freed a French teacher who had been convicted of espionage after the presidential election.
France has denied any deal with Iran to secure Clotilde Reiss's release.
Vakili Rad's lawyer, Sorin Margulis, also denied any deal. "This must not be seen as an exchange," he said, adding that Ms Reiss's arrest had only delayed his client's release.
Vakili Rad was convicted in 1994 of assassinating Bakhtiar, who had fled Iran after the Islamic Revolution of 1979.
Bakhtiar was the final prime minister to serve under Muhammad Reza Pahlavi, heading the regency council the Shah set up when he left Tehran at the start of 1979. He fled to Paris in 1980.
Shapour Bakhtiar was the last prime minister to serve under the Shah
Vakili Rad was convicted of stabbing and strangling him after gaining access to his house in Suresnes, a suburb in western Paris.
Two alleged accomplices were never caught.
Vakili Rad became eligible for parole last year, and the French interior minister signed an order for his deportation on Monday.
A French decision earlier this month to release an Iranian engineer, Majid Kakavand, had also fuelled speculation about a possible deal to secure Ms Reiss's freedom.
Mr Kakavand had been detained for the alleged illegal export of electronic parts for use by Iran's military.
The US had wanted to extradite him, but a French court rejected the request.
Ms Reiss had been sentenced to 10 years in prison before having her prison term commuted to a fine of $285,000 (£190,000). She arrived back in France on Sunday.