US Secretary of Defense Lloyd Austin spoke with Israeli Minister of Defense Yoav Gallant earlier Thursday about “regional threats and Iran’s destabilizing actions in the Middle East,” according to a Pentagon readout.

The call happened before Israel carried out a strike inside Iran. The Pentagon readout does not mention any discussion of Israel’s plans to attack.

Austin also discussed “the importance of increasing and sustaining the flow of humanitarian aid to Gazan civilians, including via the new route from Ashdod Port in Israel,” the readout said.

CNN reported Thursday night that Israel had told the US that it would be retaliating against Iran in the coming days, according to a senior US official.

Iran’s air defense systems were activated in several regions as a precaution against potential aerial threats, according to the latest report from state news agency, IRNA.

Extensive checks in Isfahan, a critical central province with significant nuclear facilities, indicate that all sensitive military and security installations remain secure, with no incidents reported.

Furthermore, IRNA said there have been no activations of missile defense systems.

Three drones “have been successfully shot down by the country’s air defence, there are no reports of a missile attack for now,” Iran’s National Cyberspace Center spokesman, Hossein Dalirian, said on X.

The Australian Government Department of Foreign Affairs and Trade (DFAT) urged its citizens in Israel to “depart if it’s safe to do so.”

The department warned that “military attacks may result in airspace closures, flight cancellations & diversions & other travel disruptions.”

It is concerned that Tel Aviv’s Ben Gurion International Airport “may pause operations due to heightened security concerns at any time, & at short notice.”

The Israeli military said they “don’t have a comment at this time,” when asked by CNN about reports of explosions in Iran.

Israel carried out a strike inside Iran early Friday local time, a US official tells CNN. The target is not nuclear, the official said.

The US also said it had advance warning of Israel’s retaliation against Iran but “didn’t endorse” it, a senior US official said.

The strike against Iran early Friday is just the latest in an intensifying and uncertain series of attacks in the Middle East.

Should a tit-for-tat between Israel and Iran develop, the conflict between the nations threatens to get “very grim very quickly,” an international relations expert told CNN.

Iran could choose to target Israel through proxies in Lebanon and Iraq, as well as with the help of Hamas in Gaza and the Houthi militant group in Yemen, Ghosh said.

Friday’s strikes have pitched the conflict into “unknown territory,” he said.

CNN Global Affairs Analyst Kim Dozier said this “escalation ladder” between the countries could lead to “something really dire — an all-out back and forth between the two.”

Israel had told the US on Thursday it would be retaliating against Iran in the coming days, a senior US official said.

“We didn’t endorse the response,” the official said.

Israel had been weighing a response to Iran’s weekend airstrikes targeting the Jewish state, most of which were intercepted.

Israel has carried out a strike inside Iran, a US official tells CNN. The attack came just hours after Iranian Foreign Minister Hossein Amir-Abdollahian told CNN in an interview that if Israel takes any further military action against it would be “immediate and at a maximum level.”