Iran has sentenced a former deputy defence minister who holds dual Iranian-British citizenship to death on charges of spying for the UK, Iranian state media reported on Wednesday.
Britain described the death sentence on Alireza Akbari as politically motivated and called for his immediate release.
Akbari was a close ally of Ali Shamkhani, who is the secretary of Iran's Supreme National Security Council and served as Defence Minister from 1997 to 2005, when Akbari was his deputy.
"He was one of the most important agents of the British intelligence service in Iran who had access to some very sensitive centres in the country," Iran's Interior Ministry said. "Akbari had fully knowingly provided information to the enemy's spy service."
British foreign minister James Cleverly called for Akbari to be freed.
"Iran must halt the execution of British-Iranian national Alireza Akbari and immediately release him," Cleverly wrote on Twitter. "This is a politically motivated act by a barbaric regime that has total disregard for human life."
Akbari's family have told BBC Persian that authorities are preparing to execute him.
Alireza Akbari's wife, Maryam, said she had been asked to come to his prison for a "final meeting" and that he had been moved to solitary confinement.
BBC Persian also broadcast an audio message on Wednesday from Akbari in which he said he was tortured and forced to confess on camera to crimes he did not commit.
He said he was living abroad a few years ago when he was invited to visit Iran at the request of a top Iranian diplomat who was involved in nuclear talks with world powers.
Once there, he said, he was accused of obtaining top secret intelligence from Shamkhani "in exchange for a bottle of perfume and a shirt".
Hours after the audio message was broadcast, the Iranian judiciary's Mizan news agency confirmed for the first time that Akbari had been found guilty of espionage, and that the Supreme Court had rejected his appeal.
Akbari, who was arrested in 2019, had been close to Shamkhani since the Iran-Iraq war in the 1980s.
His death sentence has been upheld by Iran's Supreme Court, Nournews, an Iranian news agency affiliated to the country's top security agency, reported.
"Our priority is securing his immediate release and we have reiterated our request for urgent consular access," a UK Foreign Office spokesperson said.
Iran, which has been at odds with Western powers including Britain over what it calls their interference in its internal matters during months of anti-government protests, does not recognise dual nationality status.
- Reuters / BBC