Iran has handed down the death penalty to a former senior defense official over spying for British intelligence services, Tehran's judicial news agency Mizan Online reported on Wednesday.
The former deputy Iranian defense minister was arrested in 2019 and convicted of espionage on behalf of the UK. Akbari denied the charge.
"Ali Reza Akbari was sentenced to death for corruption on earth and for harming the country's internal and external security by passing on intelligence," Mizan Online reported.
Citing a statement from Tehran's intelligence ministry, Mizan said Akbari had become a "key spy" for the UK's "Secret Intelligence Service" — MI6.
UK: 'Politically motivated act by a barbaric regime'
British Foreign Minister James Cleverly said the death sentence was "a politically motivated act by a barbaric regime that has total disregard for human life."
"Iran must halt the execution of British-Iranian national Ali Reza Akbari and immediately release him," he wrote on Twitter.
Alongside UN observers, Akbari led the implementation of a 1988 cease-fire between Iran and Iraq following an eight-year conflict.
Iran is thought to be second only to China in the number of annual executions, according to human rights groups, including Amnesty International.
Belgian citizen given 40 years for 'espionage'
Although Akbari's arrest and prosecution predate the current protests in Iran, news of his sentence coincides with a series of draconian punishments against people accused of crimes connected to the public unrest.
On Tuesday, Iran said a Belgian citizen had been sentenced to 40 years in prison and 74 lashes over charges of "espionage," coordinating with the US government, money laundering, and currency smuggling.
Belgian aid worker Olivier Vandecasteele was also fined $1 million (€931,030), the Iranian judiciary website said on Tuesday.
Brussels lambasted the sentence, vowing to summon the Iranian ambassador on Tuesday in protest.