Institute for the Study of War - Iran Update Special Report, May 31, 2026

 

May 31, 2026 Data Cutoff: 2:00 PM ET  Parker Hempel, Ben Schmida, Will Doran, Nidal Morrison, Avery Borens, and Annika Ganzeveld TOPLINES US President Donald Trump has requested several amendments to the draft US-Iran memorandum of understanding (MoU) as the United States and Iran remain at odds over key issues. A senior Trump administration official and a second unspecified source told Axios on May 30 that Trump requested several amendments to the draft MoU. The officials said that Trump specifically requested amendments to the draft’s text about how and when the United States would secure Iran’s highly enriched uranium (HEU). The current draft MoU states that Iran would commit to not pursue a nuclear weapon but does not contain any Iranian commitments to hand over Iran’s HEU or halt enrichment. The current draft states that the United States and Iran would discuss nuclear issues during a 60-day period after the parties sign the MoU. Iranian officials have repeatedly insisted that Iran will not suspend uranium enrichment or transfer its HEU from Iran. Anti-regime media, citing an unspecified informed source, claimed on May 31 that President Masoud Pezeshkian has submitted a resignation letter to Supreme Leader Mojtaba Khamenei. Pezeshkian reportedly warned in an “unprecedented and critical tone” that the IRGC is wielding an outsized role in the regime. ISW-CTP cannot independently verify this report. Iranian state media denied this report and no Iranian officials have confirmed this claim at the time of this writing. Iran continues to use the Caspian Sea and overland transit routes to try to offset reduced maritime trade caused by the US blockade on Iranian ports, but these alternative routes offer less capacity and efficiency than commercial shipping through the strait. Deputy Parliament Speaker Haji Babaei stated on May 31 that Iran is avoiding the US blockade on Iranian ports by using alternative routes and land corridors. He claimed that Iran now imports at least 50 percent of basic goods through the Caspian Sea and argued that Iran must continue to develop alternative trade routes to ensure Iran’s economic security under the blockade. Iranian state media separately claimed on May 31 that Iran has imported over 20.5 million tons of goods this year, which marks an increase compared to the past two years. Iranian state media added that Indian goods are transported by rail and road to Iran via Armenia, Turkey, and Azerbaijan. An economics expert told Radio Free Europe (RFE) on May 6 that alternative routes can supply Iran with goods but cannot fully replace a maritime container-based economy. A former US economic adviser separately told RFE on May 6 that trucking is more expensive than shipping and that Caspian Sea import throughput is constrained by limited port and fleet capacity, which the former adviser stated may raise costs and inflation in Iran. READ THE FULL UPDATE KEY TAKEAWAYS US President Donald Trump has requested several amendments to the draft US-Iran memorandum of understanding (MoU) as the United States and Iran remain at odds over key issues. Officials said that Trump specifically requested amendments to the draft’s text about how and when the United States would secure Iran’s highly enriched uranium (HEU). A second informed source told Axios that Trump also requested changes to the draft MoU’s text on the Strait of Hormuz. Three US officials separately told the New York Times on May 30 that Trump is concerned about parts of the draft MoU that would involve the United States unfreezing Iranian funds. Islamic Revolutionary Guards Corps (IRGC)-affiliated media argued that it would be better to not reach an agreement than for Iran to accept a “bad deal” that failed to secure Iranian interests. Anti-regime media, citing an unspecified informed source, claimed on May 31 that President Masoud Pezeshkian has submitted a resignation letter to Supreme Leader Mojtaba Khamenei. ISW-CTP cannot independently verify this report. Iranian state media denied this report and no Iranian officials have confirmed this claim at the time of this writing. CONTINUE READING DONATE ISW takes no US or foreign government funding. We are powered by the support of individuals like you. Help us stay independent and impactful. Website | Jobs | Internships Follow ISW on social media: Facebook | X | YouTube | Instagram | LinkedIn | Threads | Bluesky © 2026 Institute for the Study of War and AEI’s Critical Threats Project. All rights reserved. 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