How a possible thaw with the West is viewed in Iran – on the factory floor, at Friday prayers, and in government suites.
Tehran's lead negotiator in the landmark accord is the face of domestic efforts to sell the deal to ordinary Iranians. Hardliners are watching intently.
Iranian officials frequently used Twitter to get out their message during talks, particularly when they disagreed with US claims.
Iran and the US hailed an accord that temporarily halts Iran's nuclear program and offers sanctions relief – but holds major political risks for both President Obama and Iran's President Rouhani.
The failure of recent talks between Iran and world powers on its nuclear program could help hardliners opposed to a deal. Negotiators are scrambling to prevent that.
French objections helped block talks that appeared close to a preliminary deal. Kerry warned each day of delay meant 'Iran will continue to enrich, and Iran will continue to put centrifuges in.'
A first-phase nuclear deal with Iran appeared imminent, spurring Secretary of State John Kerry and European foreign ministers to rush to Geneva.
When Iranian hardliners draped Tehran with anti-US banners, Foreign Minister Zarif asked the world to understand that, like the US tea party, the groups don't speak for everyone.
Turnout at Iran's annual commemoration of the embassy seizure today was the largest in years. But do hardliners have the clout to disrupt talks on Iran's nuclear program?
Iranian Foreign Minister Mohammad Javad Zarif warned threats and sanctions are no solution to his country's nuclear program.