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

Fire injures at least 2; incident comes amid escalating tensions with Israel, which Tehran has blamed for an earlier blast at Natanz nuclear plant

Moscow refuses to comment on the leaked remarks from Iran's top diplomat, as world powers try to salvage 2015 deal

Incident follows a series of events attributed to a shadow war between Iran and Israel, including attacks on regional shipping and sabotage at Iran's Natanz nuclear facility

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

Britain, France and Germany urge all sides 'to seize the diplomatic opportunity' to salvage the 2015 nuclear deal

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

Ongoing covert actions against Tehran's nuclear program risk causing a rupture with Biden while unlikely to stop a new agreement that both Washington and Tehran want

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

But EU chief negotiator says 'much more hard work' needed to rescue 2015 deal; top Israeli security officials to head to US to lobby for improvements to the pact