Iran and the US: When friends fall out

Under the glittering chandeliers and gilt-panelled walls of a Hapsburg palace in Vienna, Iranian and American negotiators are locked in conflict talks.

At stake is the revival of the historic 2015 nuclear deal, which sought to resolve a key element in more than 40 years of US-Iran enmity and which Donald Trump, then the US president, abruptly withdrew from in 2018.

Trump set the United States once again on a path to regime change in Tehran, and plunged the Iranian economy, poised to reap the benefits of the agreement, into free fall.

Looming over the talks is the prospect of what failure might hold: a potential US or Israeli strike on Iran’s nuclear facilities that could unleash a wave of violent retaliation across the Middle East by Iran and its allies.

Read more: Iran and the US: When friends fall out