Addressing UN atomic watchdog, Ali Akbar Salehi says accord ‘caught in quasi-stalemate situation’ since US pullout, but asserts there’s broad agreement it merits fighting for

Rafael Grossi, head of International Atomic Energy Agency, says Tehran's granting inspectors access to two disputed sites could build cooperation

Tehran's nuclear chief says work has already begun on facility to replace Natanz, damaged in mysterious July 2 explosion

UN inspectors gain access to one of two sites where undeclared nuclear activity may have taken place in the early 2000s; second site to be inspected later this month

Representatives meeting in Vienna vow to preserve accord; Russia takes swipe at US for trying to dictate terms despite withdrawing from deal in 2018

Amid tensions with US, Tehran 'voluntarily providing the IAEA with access' to locations in central Iran and close to capital

Spokesman for Iran's nuclear body says Tehran may grant UN agency approval to inspect two sites, provided it does not subsequently demand to see more

Visit comes as the US is pushing to 'snapback' UN sanctions on Iran for allegedly violating its 2015 nuclear deal with world powers

Tehran's envoy to IAEA says Rafael Grossi coming at Islamic Republic's invitation, without link to Trump's attempts to trigger 'snapback' mechanism

Focus will be on sites thought to be from early 2000s, before Iran signed the 2015 nuclear deal with world powers, which Tehran says IAEA inspectors have no legal basis to inspect