The Biden administration says it had no role in the explosion on Sunday at an Iranian uranium enrichment facility. Iran has blamed Israel and vowed to take revenge. Why it matters: The administration is attempting to negotiate a return to the 2015 Iran nuclear deal, with a second round of indirect talks set to start on Wednesday. The timing of the incident, along with several recent Israeli strikes on Iranian ships, could make Biden's diplomatic challenge more difficult. What they're saying: "We have seen reports of an incident at the Natanz enrichment facility in Iran. The United States had no involvement, and we ... (full story)