International Atomic Energy Agency chief says move is 'very, very important... in particular in the context of the possibility of the revival of JCPOA'

IAEA director Rafael Mariano Grossi traveling to Tehran for first time in a year, amid reports that Iran has accumulated enriched uranium to 84% purity

Tehran announces trip by Rafael Grossi following revelation that IAEA inspectors found uranium enriched to 84% purity, the closest Iran has come to weapons-grade

WSJ reports particles of near-weapons-grade uranium could have been accidentally produced during recent trials in speeding up the enrichment process at Fordo plant

Report says inspectors from UN atomic agency made discovery last week, are probing if move was intentional; Tehran previously known to have enriched to 60%

Country's atomic agency says it has provided 'explanations' about altered configuration of devices and the matter has been resolved

Tehran's atomic agency chief hopes to make 'effective progress' with IAEA on nuclear material found in 3 undeclared sites

Secretary-General Guterres says IAEA nuclear watchdog's independence is 'essential' after Iran demands an end to probes, again stalling negotiations

As nuclear deal talks hit fever pitch, IAEA report seen by Reuters says Tehran continuing 5% enrichment on IR-6 centrifuges at its underground Natanz plant

IAEA staff aim to protect Zaporizhzhia plant, Europe's biggest, as top EU official accuses Russia of 'gambling with the nuclear security' by not demilitarizing the area