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 have nothing to add to speculation about the causes," a senior Biden administration official said.

• Iranian Foreign Minister Javad Zarif blamed Israel for the explosion, which resulted in damage to centrifuges used to enrichment uranium. He said the incident would not affect the nuclear talks, but “we will take our revenge against the Zionists.”
• Ali Akbar Salehi, the head of Iran's atomic energy organization, denied a New York Times report that the explosion caused such severe damage that it will take 9 months to repair. Salehi said uranium enrichment continues and the damaged centrifuges will soon be replaced.
• Iranian media reported that the intelligence services were investigating the incident, and one arrest had already been made.

Meanwhile, U.S. Secretary of Defense Lloyd Austin met this morning in Jerusalem with Prime Minister Benjamin Netanyahu.

• Speaking alongside Austin, Netanyahu stressed that Iran was the gravest threat in the region and that Israel would never allow Iran to obtain a nuclear weapon.
• Austin stressed the U.S. commitment to Israel's security but did not mention Iran.