Iran has executed a former defense official sentenced to death on charges of spying for Britain.
Iran's judiciary announced on Saturday the execution of Alireza Akbari, a former Iranian deputy defense minister.
Akbari was arrested on suspicion of undermining Iran's national security by spying for the British intelligence service, MI6.
The Iranian judiciary said in a statement that Akbari had leaked classified information on Iran's internal affairs, diplomacy, and national defense in return for British citizenship and a large amount of money.
The leak was said to have included information on Iran's top nuclear scientist, Mohsen Fakhrizadeh, who was assassinated in 2020.
Fakhrizadeh was believed to have played a major role in the country's nuclear development.
Britain's Foreign Secretary James Cleverly said in a statement that the execution is "a barbaric act that deserves condemnation in the strongest possible terms."
Cleverly also said, "Through this politically motivated act, the Iranian regime has once again shown its callous disregard for human life. He stressed, "This will not stand unchallenged."
Cleverly added that the British government will summon the Iranian Charge d'Affaires to make clear its disgust at Iran's actions. The UK's foreign secretary has temporarily recalled the UK's ambassador to Iran.
Relations have deteriorated as Iran claims Britain has incited anti-government protests in the country, while London condemns Iranian authorities for sentencing protesters to death.