LONDON: Britain is reassessing its backing of the Iran nuclear deal after Tehran executed a British Iranian dual national, drawing strong condemnation from Western governments.

Alireza Akbari, 61, was hanged after being convicted of 鈥渃orruption on earth and harming the country鈥檚 internal and external security by passing on intelligence.鈥� When or where the execution took place is unknown.

The execution has led to a huge escalation in tensions between the West and Iran, which were already running high over Tehran鈥檚 crackdown on protests over the death in custody of Mahsa Amini and the regime鈥檚 military support for Russia鈥檚 invasion of Ukraine.

The UK has been a key player in talks on reviving the nuclear deal, which placed significant restrictions on Iran鈥檚 nuclear program in exchange for sanctions relief.

Senior government sources said that the 鈥渓andscape鈥� has changed significantly since the negotiation process began and as such Britain is now reviewing its options regarding future involvement in reviving the deal, The Sunday Telegraph reported.

They said the relationship with Tehran has been under pressure in recent months because of the regime鈥檚 harsh repression of anti-government protests.

UK Prime Minister Rishi Sunak said that he was 鈥渁ppalled鈥� by the execution.

鈥淭his was a callous and cowardly act, carried out by a barbaric regime with no respect for the human rights of their own people,鈥� Sunak said.

Foreign Secretary James Cleverly warned that the execution would not go unchallenged, before announcing sanctions on Iran鈥檚 prosecutor general to underline Britain鈥檚 鈥渄isgust.鈥�

Britain said it would summon Tehran鈥檚 envoy and in response, Iran summoned the British ambassador to protest against what it described as 鈥渦nconventional interventions.鈥�

France鈥檚 Foreign Ministry also condemned the execution 鈥渋n the strongest terms鈥� and said that the killing 鈥渃annot go unanswered.鈥� President Emmanuel Macron denounced Akbari鈥檚 execution as a 鈥渉einous and barbaric act.鈥�

Tehran has been accused of using the talks as cover to ramp up work on its nuclear program with a view to obtaining a bomb 鈥� a charge that it denies.