In a report to member countries, IAEA estimates figure at 33 kilograms; total stockpile assessed at 3,197, though it could not verify exact size due to limitations on inspectors

As Europe and US lose patience, Tehran believes it has scored points in Vienna by ensuring discussion of sanctions relief takes place in next round of talks

Britain, France and Germany call latest request from Tehran to pause talks 'disappointing;' UN nuclear chief casts 'doubt' on missing Iran data from cameras

UK, Germany, France say UN atomic agency representatives subject to intimidation: 'This is unacceptable and unprecedented'

Rafael Grossi says he 'could not agree' on points of contention during meetings in Tehran

Tehran says negotiating team heading to Vienna with 'a serious will to lift the sanctions,' urges other parties to 2015 deal 'to reach a practical and comprehensive agreement'

UN agency confirms inspectors turned away when they try to replace surveillance equipment at Karaj centrifuge assembly facility

After WSJ reports that security officers at Natanz facility inappropriately touched its female auditors, ordered them to remove clothing, IAEA calls treatment unacceptable

Head of UN nuclear watchdog upbeat after reaching a deal in Tehran to renew inspectors' access to nuclear site surveillance equipment

Announcement buys time for Tehran ahead of watchdog meeting this week where Western powers were set to argue for Tehran to be censured over its lack of cooperation