A day before nuclear talks are due to resume, British Foreign Secretary Lise Trace called on Iran to return to the nuclear deal, saying it was the "last chance" for them to come back into compliance.

"This is really Iran's last chance to return to the deal and I strongly urge them to do so because we are determined to work with our allies to prevent Iran from acquiring nuclear weapons," Trace was quoted as telling the Chatham House think-tank.

"So they should return to the Joint Comprehensive Plan of Action, because it is in their interest to do so," she added, referring to the 2015 nuclear deal.