Iranian foreign minister tweets link to Guardian report that construction work at top-secret Israeli facility visible in satellite imagery, asks why world leaders are silent

Tehran has threatened to suspend some nuclear inspections if US fails to lift punitive measures

IAEA visited the 2 locations last summer after Iran tried for months to block it, Reuters reports; finding could complicate US return to negotiations with Tehran

Accord signatories state commitment to ensuring 'Iran can never develop nuclear weapon,' warn Tehran it would be 'dangerous' to limit UN nuclear agency inspections

IAEA head to visit Tehran, ahead of Iranian intention to end snap inspections

Iranian foreign ministry says it'll prevent certain visits by UN watchdog if other parties to nuclear accord 'fail to meet their obligations'

Diplomats tell Wall Street Journal UN agency seeking explanations for radioactive materials found in locations Tehran blocked access to last year

Foreign Ministry spokesman says that despite new law mandating an end to certain types of scrutiny by IAEA monitors, cooperation will continue

Tehran nuclear chief issues warning amid heightened tensions day ahead of one-year anniversary of Soleimani's killing in US drone strike

At such level, uranium is a relatively short jump from weapons-grade material; signatories to nuclear deal have urged Tehran not to squander chance to salvage the 2015 accord