Iran Update, June 4, 2025
Iranian Supreme Leader Ali Khamenei categorically rejected the recent US nuclear proposal because the proposal would require Iran to eventually halt all uranium enrichment on Iranian soil.[1] Iran’s continued rejection of the US demand for zero uranium enrichment could cause the US-Iran nuclear negotiations to collapse. Axios reported on June 2 that the US proposal would allow Iran to enrich uranium at three percent on Iranian soil during the establishment of a regional nuclear consortium.[2] The United States reportedly seeks to establish the consortium outside of Iran. Iran would be required to halt all enrichment after the establishment of the consortium. Khamenei delivered a speech on June 4 in which he stated that enrichment in Iran “is a red line.”[3] Khamenei claimed that a nuclear industry without enrichment is “practically worthless” and emphasized that Iran would not become “dependent” on foreign countries for uranium.[4] Under the US proposal, Iran would receive uranium for civilian nuclear purposes as part of the regional consortium but would not be allowed to independently enrich uranium on Iranian soil after the consortium is formed.
Iran may accept the establishment of a regional nuclear consortium if it operates on Iranian soil. An unspecified senior Iranian official told Axios on June 3 that Iran is open to the consortium model, but only if the consortium’s enrichment facility is located in Iran.[5] Two unspecified Iranian officials separately told the New York Times on June 4 that Iran is planning to “bargain” for the regional consortium to be based on Kish or Gheshm islands in the Persian Gulf to maintain its right to enrichment on Iranian soil.[6] An unspecified Arab diplomatic source told Israeli media on June 3 that the United States may propose placing the consortium on one of the disputed islands—Abu Musa, Greater Tunb, or Lesser Tunb.[7] Iran seeks for the regional consortium to be based on Kish or Gheshm islands, rather than the disputed islands, given that the former are internationally recognized as Iranian territory while the latter are claimed by both Iran and the United Arab Emirates.
The Iranian officials speaking to the New York Times added that Iran is open to the consortium idea because Iran “does not want talks to fail.”[8] It is in Iran’s interest to prolong the nuclear talks, given that it likely calculates that prolonging the talks will delay or prevent snapback sanctions and a potential US or Israeli strike on its nuclear facilities. US President Donald Trump accused Iran of “slow-walking [its] decision” after Khamenei rejected the US proposal on June 4. Iran has not yet submitted a formal response to the US proposal, which could reflect internal debates in Iran about how to reject the US zero enrichment demand in the proposal while also ensuring that the negotiations do not collapse.
Likely Iranian-aligned militants launched a small-scale rocket attack from southwestern Syria into the Israeli-controlled Golan Heights on June 3.[9] This attack marks the first time that militants have attacked Israel from Syrian territory since the fall of the Assad regime in December 2024.[10] Militants launched two rockets from Tasil, Daraa Province, into the southern Golan Heights.[11] The Israel Defense Forces (IDF) briefly operated in Tasil in April 2025.[12] Israeli media reported on June 3 that the rockets landed in open areas and did not cause any casualties.[13] The IDF launched several retaliatory air and artillery strikes targeting Syrian military sites and towns in southwestern Syria on June 3.[14] The targeted military sites included the new Syrian army’s 121st Brigade base near Kanaker, Rif Dimashq Province, and the 175th Brigade base near Izraa, Daraa Province.[15]
Two likely Iranian-aligned groups separately claimed responsibility for the June 3 rocket attack.[16] Neither group has previously conducted any attacks targeting Israel. The Martyr Muhammad al Deif Brigades claimed responsibility for the attack and released a video that reportedly showed the rockets landing in the Golan Heights.[17] The Martyr Muhammad al Deif Brigades is a Hamas-aligned Palestinian resistance group that announced its formation on June 3.[18] The Islamic Resistance Front of Syria-the First of the Brave also claimed responsibility for the attack and published a video of the alleged rockets in their launching positions on June 3.[19] The Islamic Resistance Front of Syria-the First of the Brave is an anti-Israel militia formed in January 2025 that uses iconography widely associated with or inspired by the Iranian Islamic Revolutionary Guards Corps.[20] The Islamic Resistance Front of Syria-the First of the Brave Spokesperson Abu al Qasim gave a speech on June 4 in which he stated that the Syrian government has become a “defeatist project demanding normalization” with Israel to gain “some personal and moral privileges.”[21] Qasim stated that this attack was a “clear warning” and that the group will conduct additional attacks targeting Israel in the future.[22] Qasim also noted that the group will attack “whoever tries to strip Syria of its resistance identity.”[23]
This attack may have been an attempt to fuel tension between Israel and Syria in order to undermine recent deconfliction and diplomatic efforts between the two countries. Israeli Defense Minister Israel Katz posted on X on June 3 that Israel holds Syrian President Ahmed al Shara “directly responsible for every threat” and attack on Israel from Syrian territory.[24] The IDF also stated on June 3 that the Syrian transitional government will continue to bear consequences “as long as hostile activity continues from its territory.”[25] The Syrian Foreign Affairs Ministry issued a statement that reaffirmed that Syria “has not and will not” pose a threat to any country in the region.[26] The ministry added that some external actors are seeking to destabilize the region to advance their own interests.[27] Israel has repeatedly expressed concern regarding threats to Israel from Syria since the fall of the Assad regime in December 2024.[28] The IDF has conducted ground and air operations in southern Syria since December 2024 with the aim of eliminating these threats, including Iranian-backed networks in Syria.[29] The Syrian transitional government has repeatedly called on Israel to withdraw from Syrian territory to the 1974 deconfliction line.[30] Israel and Syria have taken steps in recent weeks to ease tensions. Several unspecified sources told Western media on May 27 that Israeli and Syrian officials are holding direct talks on joint security and “broader political understandings” to calm tensions and prevent further conflict.[31] Syrian President Ahmed al Shara also reportedly expressed willingness to normalize relations with Israel during meetings with US officials in April 2025.[32] Renewed tension between Israel and Syria could undermine the countries’ recent efforts to prevent military escalation and reach a political and diplomatic understanding.
https://www.understandingwar.org/backgrounder/iran-update-june-4-2025
Iran Update, June 5, 2025
Russia continues to position itself as a mediator in the US–Iran nuclear negotiations. Russia’s mediation of the US–Iran talks would be very unlikely to secure US interests given Russia’s alignment with Iran. US President Donald Trump stated on June 4 that Russian President Vladimir Putin offered to “participate” in the US–Iran nuclear negotiations.[1] Russia’s offer to mediate the negotiations comes after Iranian Supreme Leader Ali Khamenei explicitly rejected a recent US nuclear proposal to Iran because the proposal would require Iran to eventually halt all uranium enrichment on Iranian soil.[2] CTP-ISW previously assessed that Iran’s continued rejection of the US demand for zero uranium enrichment could cause the US–Iran nuclear negotiations to collapse.[3] Iran and Russia have held several meetings since March 2025 to discuss the dispute between Iran and the United States over Iran’s nuclear program.[4] Russia has opposed stated US objectives in the nuclear negotiations and the recent US proposal by supporting Iran’s right to enrich uranium.[5] Russian Permanent Representative to the UN in Vienna Mikhail Ulyanov claimed in early March 2025 that Iran’s production of 60 percent enriched uranium has “no weapons risk.”[6] Iran currently has enough 60 percent enriched uranium, if enriched further, to produce nearly 10 nuclear weapons.[7] Russia’s support for Iran’s domestic uranium enrichment is inconsistent with the stated US position against uranium enrichment on Iranian soil. US President Donald Trump confirmed on June 3 that the United States maintains its position that Iran cannot enrich uranium.[8]
Iran and Russia have deepened political and military cooperation in recent years, particularly since the Russian invasion of Ukraine in February 2022. Iran has supported Russia’s invasion of Ukraine by providing Russia with Fateh-360 ballistic missiles and launchers and Shahed drones.[9] Iran reportedly purchased Russian Su-35 fighter jets in January 2025, though Russia has not yet delivered the Su-35s to Iran.[10] Russia has also supported and cooperated with Iran’s Axis of Resistance in recent years. This cooperation has included working with Iran and Iranian-backed militias to attack US forces in the Middle East.[11] Russia also supported the Axis of Resistance against Israel during the October 7 War, including by providing targeting intelligence to the Houthis to support attacks on international shipping and US vessels in the Red Sea and Gulf of Aden.[12] Iran and Russia signed a strategic cooperation agreement in January 2025, which further illustrates their close collaboration and alignment in working to erode US global influence.[13]
Senior Iranian military commanders continue to prepare for potential US or Israeli strikes on Iran. Khatam ol Anbia Air Defense Headquarters Commander Brigadier General Alireza Sabahi Fard inspected Iran’s Northern Air Defense Zone at Mehrabad Airport in Tehran Province on June 5 to evaluate military units and defense capabilities at the site.[19] Sabahi Fard also inspected air defense positions near former Supreme Leader Ruhollah Khomeini’s mausoleum in southern Tehran. Sabahi Fard may have inspected the Hazrat-e Amir Brigade Air Defense Site. The Israel Defense Forces (IDF) struck the Hazrat-e Amir Brigade Air Defense Site in October 2024.[20] The brigade is located roughly 8 miles from Khomeini’s mausoleum and about 7 miles from the Northern Air Defense Zone at Mehrabad Airport. Sabahi Fard has inspected at least 12 Iranian air defense sites across Iran since April 2025.[21]
https://www.understandingwar.org/backgrounder/iran-update-june-5-2025