All sides agreed to continue talking for four more months to try reach a final agreement.
US Secretary of State John Kerry met Irain’s Mohammad Javad Zarif on Tehran’s nuclear programme.
Six world powers are negotiating with Iran to scale back on enrichment capacity sharply.
Iran, the US, Britain, France, Germany, Russia and China included the 20 July deadline to reach a pact.
The IAEA said more work was still needed for the implementation of a series of nuclear transparency steps.
The overarching goal is to persuade Iran to scale back its nuclear programme.