The U.S. team negotiating a comprehensive nuclear deal with Iran were “not very optimistic” about the chances of a breakthrough in the talks, a senior U.S. official said Thursday, but bilateral discussions with Iran over the last 24 hours have been “constructive.” “Coming into New York, many of us were not very optimistic,” the official said. However, after discussions with Iran Wednesday evening and Thursday morning, “it is clear that everyone has come here to go to work.” The official said U.S. President Barack Obama is “open to” meeting with Iranian President Hasan Rouhani on the sidelines of the United Nations General Assembly next week but that there was no meeting scheduled. The official said “the choice is really Iran’s.” Mr. Obama and Mr. Rouhani held a historic 15-minute phone conversation at last year’s annual General Assembly meeting. Iran is negotiating a nuclear deal with the U.S. and […]