Lacking data, IAEA forced to issue estimate of uranium stockpiles; says there was likely a slowdown in enrichment after mysterious blast in April at Natanz facility

Amid talks on renewing nuke deal, IAEA said to conclude Tehran exceeding 60% enrichment cap it announced, bringing it even closer to weapons-grade level

UN atomic watchdog says just 1 cluster of UF6 machines being used at aboveground part of nuke site hit in blast blamed on Israel; older cascades said being used for 20% enrichment

IAEA records 8 new cascades at underground nuclear site hit in blast blamed on Israel; says Islamic Republic planning to add more

Ali Akbar Salehi, head of country's atomic agency, claims enrichment at key nuclear site never stopped following blast blamed on Israel

Amassing high-grade fissile material is only the first step toward an atomic weapon, and Tehran's latest violation of the JCPOA does not substantially change the timeline

Chinese envoy says sides agreed to 'pick up their pace' in talks to save 2015 deal, and 'work on sanctions-lifting as well as other relevant issues'

But Olli Heinonen says the Islamic Republic would still need months to make a bomb if it did so, after Tehran announces it has begun enriching uranium to 60%

Britain, France, and Germany say move is 'a serious development' amid ongoing negotiations to revive 2015 nuclear deal

Iranian envoy to UN atomic agency says Islamic Republic will start enriching at previously unseen levels by next week