Iran official upbeat over nuclear talks, top delegate cautious
(Reuters) --- Iranian government spokesman Ali Rabiei said on Tuesday he was optimistic over Tehran reaching an agreement soon at talks with world powers to revive a 2015 nuclear deal, although Iran's top negotiator cautioned that serious issues remained.
Iran and global powers have held several rounds of negotiations since April in Vienna, working on steps that Tehran and Washington must take on sanctions and nuclear activities to return to full compliance with the nuclear pact.