Iran has been condemned by the UK government over the planned execution of a British-Iranian dual national.
Foreign Secretary James Cleverly appealed to Iranian authorities not to go ahead with the execution of Alireza Akbari, a former senior defence official reportedly charged with spying for British intelligence.
Mr Cleverly tweeted: "Iran must halt the execution of British-Iranian national Alireza Akbari and immediately release him.
"This is a politically motivated act by a barbaric regime that has total disregard for human life."
Mr Akbari was arrested in 2019 and accused of espionage for MI6 related to past nuclear talks between Iran and western nations, according to reports.
He has denied the charge and said he was tortured and forced to confess on camera to crimes he did not commit, BBC Persian reported.
Mr Akbari’s wife Maryam told the service she was invited to a "final meeting" at the prison where he has been put in solitary confinement, an apparent sign that an execution is imminent.
Commons Foreign Affairs Committee chairwoman Alicia Kearns accused the Iranians of seeking to "weaponise" dual nationals, as anti-government protests convulse the country.
"It is another horrifying example of the Iranian regime - because they feel they are cornered, because there is such significant pressure from sanctions - weaponising British nationals and industrialising hostage-taking," she told BBC Radio 4’s PM programme.
She said Mr Akbari may have been singled out by the regime because of his closeness to a leading Iranian moderate, who has led calls for dialogue and discussion.
She said: "I wonder if this is an effort to undermine that individual. It is also a chance for the Iranians to reiterate their narrative that the British government, the American government, are trying to undermine the regime and overthrow the Iranian regime."
After recent executions of anti-government protesters, Ms Kearns said western countries should respond with fresh sanctions.
"Every time the Iranian government assassinates an individual involved in the protests, there should be sanctions applied by western governments the next day to make the point that we stand by those protesting for the basic rights of Iranians, otherwise we are showing no meaningful support to them," she added.
Tehran has detained a number of dual and foreign nationals in recent years, including British-Iranian national Nazanin Zaghari-Ratcliffe, who was held in 2016 and released last year.
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Amnesty International called the reports of Mr Akbari’s death sentence “distressing and deeply concerning” and urged the Government to do more to prevent the execution. Freshta Sharif, Amnesty International UK’s individuals at risk campaign manager, said: “There’s a longstanding pattern of British-Iranians being arrested, mistreated and arbitrarily jailed by the Iranian authorities – in cases sometimes amounting to state hostage-taking – but an execution would represent a terrifying intensification of this process of using foreign nationals as diplomatic pawns.” She added that the UK has “a weak record when it comes to lobbying for the release of arbitrarily jailed Britons in Iran”. “Ministers must be able to show they have a clear plan for ensuring the threat of execution is lifted from Alireza and that allegations he was tortured and forced to falsely confess are fully investigated.” The Foreign, Commonwealth and Development Office has been contacted for comment.