MOSCOW — After two grueling days of nuclear negotiations, diplomats from Iran and six world powers agreed on at least one thing: they were not yet ready to let the recently re-launched diplomatic process collapse.
That prospect had loomed over the third round of Iran nuclear talks this year, as Iranian negotiators for the first time gave a detailed response to an international proposal asking it to halt enriching uranium to 20 percent of the isotope needed for nuclear explosions. But while Iran engaged in the most substantive discussion of its nuclear program to date, Western diplomats said, the discussions also revealed daunting gaps in the two sides’ positions and worldviews that made some diplomats question whether Iran was serious about the negotiations.
