Latest round of Iran nuclear talks end in Vienna: official

VIENNA: -A fourth round of talks between Iran and six world powers aimed at defusing the face-off over Tehran´s nuclear programme ended Friday after the US had voiced concern about lack of progress.

"This round of E3/EU+3 talks with Iran has now ended," Michael Mann, spokesman for EU foreign policy chief and the six powers´ lead negotiator Catherine Ashton, said in a tweet.