VIENNA—Efforts to bring the United States back into the 2015 deal on Iran’s nuclear program stepped up a gear Tuesday as Iran and the five world powers still in the accord met in Vienna while the United States is due to start indirect talks with Tehran.
Following the closed meetings of the signatories to the deal, known as the Joint Comprehensive Plan of Action, Russia’s delegate, Mikhail Ulyanov, tweeted that the initial talks were “successful.”
