Iran’s ultraconservative President Ebrahim Raisi came to power a year ago amid attempts to revive a 2015 nuclear deal between Tehran and world powers.
The accord gave Iran sanctions relief in exchange for curbs on its nuclear programme to guarantee that it could not develop an atomic weapon something it has always denied seeking.
Former US president Donald Trump dumped the deal in 2018 and began reimposing painful economic sanctions, prompting Iran to start stepping back from its commitments.
In April 2021, with President Joe Biden in the White House, talks on rescuing the accord began in Vienna.
But they have stalled since March amid differences between Tehran and Washington on several issues.
