Washington permits Mohammad Javad Zarif to travel to New York, forbids him from moving beyond six blocks of Tehran's UN mission in Midtown Manhattan

Foreign Secretary Jeremy Hunt asserts London not seeking escalation of tensions with Tehran, but wants assurances ship not heading for Syria

'Cooler heads prevailed' source tells Reuters, weeks after Mnuchin said new penalties on the foreign minister would be announced in coming days

Tehran warns that the last time pair tried to stamp out country's uranium enrichment program, it only increased '100-fold'

FM Zarif says talk show 'went against national interests' for segment detailing covert delivery of 1m barrels of crude oil to China in defiance of US sanctions

As accord teeters, Iranian president says Tehran will move to refine radioactive element beyond 2015 deal's 3.67% cap

'Not good!' US leader adds in tweet, after Tehran announces it has breached limit on uranium stockpile

US national security adviser warns only purpose of increased production of enriched material is to reduce breakout time needed to produce nuclear weapons

Israel urges European states to sanction Tehran; Russia voices regret, but blames US pressure; UN says Iran must stick to its accord commitments

As Tehran breaches cap in violation of accord and Israel calls for European sanctions, foreign policy chief says bloc still committed to 2015 agreement