The U.N. nuclear watchdog found uranium particles at two Iranian sites it inspected after months of stonewalling, diplomats say, and it is preparing to rebuke Tehran for failing to explain, possibly complicating U.S. efforts to revive nuclear diplomacy.  The find and Iran’s response risk hurting efforts by the new U.S. administration to restore Iran’s 2015 nuclear deal, which President Joe Biden’s predecessor Donald Trump abandoned. Although the sites where the material was found are believed to have been inactive for nearly two decades, opponents of the nuclear deal, such as Israel, say evidence of undeclared nuclear activities shows that Iran has not been acting in good faith. Iran’s ambassador to the International Atomic Energy Agency, Kazem Gharibabadi, declined to comment, as did […]