Annika Ganzeveld, Ashka Jhaveri, Johanna Moore, Alexandra Braverman, Kathryn Tyson, and Brian Carter

Information Cutoff: 2:00 pm ET

The Washington Post reported on April 15 that 17 Iranian officials visited a Russian air defense system factory in Yekaterinburg, Russia, in March 2023. The factory produces S-400 air defense missiles and mobile launchers, among other military equipment. The US Treasury Department’s Office of Foreign Assets Control sanctioned the company that owns the factory — NPP Start — in June 2022 for supporting Russia’s invasion of Ukraine. Unspecified intelligence officials told the Washington Post that Russia is “advancing” an agreement with Iran to supply Iran with Su-35 fighter jets. Iran has long sought, but not yet received, Su-35s in return for supplying Russia with drones. US and Middle Eastern intelligence officials assessed that delayed Iranian payments to Russia may be hindering Iran’s acquisition of the fighter jets. Russia previously provided Iran with at least two Yak-130 combat trainer aircraft in September 2023, which Iranian media framed as a “necessary prelude” for the acquisition of Su-35s.

Senior Iranian officials emphasized that Iran would strike Israel again “faster and stronger” if Israel retaliated to Iran's April 13 missile and drone attack. Iranian Deputy Foreign Affairs Minister Ali Bagheri Kani stated that Iran would respond against Israel within a “few seconds” of an Israeli attack. Iranian President Ebrahim Raisi emphasized in separate phone calls to several foreign leaders, including his Qatari and Russian counterparts, that Iran would respond “more fiercely, widely and painfully” if Israel retaliates against Iran. The spokesperson of Iran’s Parliamentary National Security and Foreign Policy Committee claimed that Iran is “ready to use weapons that [it] has not used before” during an interview with Lebanese Hezbollah-controlled media on April 16.

Key Takeaways:

• Iran: The Washington Post reported that 17 Iranian officials visited a Russian air defense system factory in Yekaterinburg, Russia, in March 2023.

• Senior Iranian officials emphasized that Iran would strike Israel again "faster and stronger" if Israel retaliates to Iran's April 13 missile and drone attack.

• Northern Gaza Strip: Palestinian sources reported that Israeli forces are operating around Beit Hanoun.

• Political Negotiations: US Secretary of State Antony Blinken said that Hamas rejected the most recent ceasefire agreement because it thought the April 13 Iranian attack on Israel would lead to a regional conflict.

• West Bank: Israeli forces clashed with Palestinian fighters in at least three locations across the West Bank.

• Southern Lebanon and Golan Heights: Lebanese Hezbollah conducted at least nine attacks from southern Lebanon into northern Israel, including a one-way drone attack targeting an Iron Dome battery.

• Iraq: Iraqi Prime Minister Mohammad Shia al Sudani continued his official visit to Washington, DC.

• Yemen: Houthi President Mahdi al Mashaat congratulated Iranian President Ebrahim Raisi for the April 13 Iranian attack targeting Israel during a phone call.

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ISW and CTP has launched an interactive map of Israeli ground operations to accompany our daily campaign assessments of the Israel–Hamas war. This product complements the daily static maps that ISW-CTP produces with high-fidelity and, where possible, street-level assessments of the war in Israel.

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