Iran Update, September 29, 2026

Data Cutoff: 2:00 PM ET

The Institute for the Study of War (ISW) and The Critical Threats Project (CTP) at the American Enterprise Institute are publishing updates Monday through Friday to provide analysis on the war with Iran and the broader Middle East. Weekday updates cover events from the past 24-hour period, whereas weekend updates are abbreviated and cover the Houthi-Saudi conflict and major breaking developments related to the war with Iran.

Key Takeaways:

• Houthi and Yemeni government-aligned forces have reportedly ordered general mobilizations to reinforce frontlines across Yemen, which may signal long-term Houthi intent to continue advances in Taiz Governorate and along the Red Sea coast and likely signals Yemeni government intent to reverse Houthi advances.
• Kataib Hezbollah Security Chief Abu Mujahid Aasaf threatened in a September 28 statement to overthrow the Iraqi federal government “by all means” if it works against Iranian and Iranian-backed Iraqi militia interests in Iraq.
• Aasaf threatened that the militias would close “the ports” of all countries participating in the “blockade” on Iranian flights and shoot down any hostile aircraft in Iraqi airspace. Aasaf's reference to the federal government's decision to close Iraqi airports to Iranian planes preceded the United States issuing a 30-day sanctions waiver for Iraqi Airways flights to carry Shia pilgrims between Iran and Najaf.

Toplines

Houthi and Yemeni government-aligned forces have reportedly ordered general mobilizations to reinforce frontlines across Yemen, which may signal long-term Houthi intent to continue advances in Taiz Governorate and along the Red Sea coast and likely signals Yemeni government intent to reverse Houthi advances. Yemeni government-aligned forces and the Houthis issued separate general mobilization orders on September 25 and 28, respectively.[i] An anti-Houthi journalist in Marib Governorate reported that the Houthis issued a general mobilization order to Yemenis in Houthi-controlled territory that includes enrollment in military training.[ii] Houthi and other Yemeni sources have not corroborated this claim at the time of this writing, however. The reported Houthi general mobilization order came after Yemeni President Rashad al Alimi issued general mobilization orders on September 25, urging Yemeni government-aligned Yemenis to join the armed forces in a national campaign to defeat the Houthis, restore state institutions, and extend government control across Yemen, including Sanaa City.[iii] The government-aligned Union of Southern Arabian Tribes announced the formation of eight Aden-based battalions to reinforce Yemeni government-aligned frontlines in southern Yemen on September 29.[iv] It is unclear if this tribal mobilization is a response to the government’s general mobilization, however. The government's mobilization marks the first nationwide mobilization ordered by the Yemeni government but a researcher at a Yemeni think tank told UK-based Saudi media on September 29 that “nothing in practice is happening” in response to the mobilization order thus far.[v] Both Houthi and Yemeni government general mobilizations are unlikely to result in an immediate or imminent deployment of frontline forces given that these forces must first receive at least some training.

The Yemeni government-aligned general mobilization order likely intends to increase the size of forces aligned with the government to reverse recent Houthi advances and the group’s consolidation of positions along the Taiz and Red Sea coastal plain axes. The government also seeks to prevent further Houthi advances, which could potentially threaten Aden City, the Republic of Yemen’s de facto capital. The Houthi general mobilization order, in contrast, may signal Houthi intent to continue advances along the same axes in order to threaten Aden and put further pressure on the Yemeni and Saudi governments to submit to Houthi demands. The Houthis may have also issued the order to bolster their forces to defend against Yemeni government operations that seek to retake territory that the Houthis have seized in recent weeks.

Both general mobilization efforts are likely also in response to heavy Houthi and Yemeni government-aligned casualties due to ongoing fighting along the Taiz and Red Sea coastal plain axes since the beginning of September.[vi] An anti-Houthi journalist in Marib reported on September 28 that Houthi forces have killed at least 256 government-aligned fighters in southern Yemen over the past three weeks and another 40 in Marib Governorate on September 28 alone.[vii] A London-based Yemen analyst, citing Yemeni government figures, separately claimed to Saudi media on September 22 that Yemeni government-aligned forces have killed approximately 2,000 Houthi fighters since the Houthi offensive began on September 9.[viii] This claim has not been independently verified, however.

Kataib Hezbollah Security Chief Abu Mujahid Aasaf threatened in a September 28 statement to overthrow the Iraqi federal government “by all means” if it works against Iranian and Iranian-backed Iraqi militia interests in Iraq.[ix] Aasaf warned Prime Minister Ali al Zaydi that Kataib Hezbollah would overthrow “any government that does not work for the benefit of the people.”[x] Aasaf likely made this threat in response to Zaydi’s efforts to disarm the militias and reduce Iranian influence in Iraq. Aasaf has recently condemned multiple government decisions, including the government’s decision to close the Baghdad and Najaf airports to Iranian planes, that constrain Iran’s ability to operate in Iraq and interfere in Iraqi affairs.[xi] Iranian-backed Iraqi actors, especially the militias, have repeatedly expressed outrage over the government’s compliance with US sanctions on Iranian airlines.[xii] Aasaf’s message came ahead of the United States’ military withdrawal from Iraq on September 30. Aasaf celebrated the withdrawal and implicitly threatened that the militias would resume attacks if US forces returned to Iraq.^[xiii]

Aasaf also threatened countries that continue to comply with US sanctions on Iranian airlines after October 1.[xiv] Aasaf said that the militias would close “the ports” of all countries participating in the “blockade” on Iranian flights and shoot down any hostile aircraft in Iraqi airspace, the latter of which may refer to any flights over Iraq by countries complying with US sanctions on Iranian airlines.[xv] Iran recently banned UAE-based airlines from flying in its airspace after the UAE banned Iranian flights.[xvi]

Aasaf's reference to the federal government's decision to close Iraqi airports to Iranian planes preceded the United States issuing a 30-day sanctions waiver for Iraqi Airways flights to carry Shia pilgrims between Iran and Najaf International Airport.[xvii] The United States and the Iraqi federal government negotiated the waiver in recent days.[xviii] Najaf houses the Imam Ali Shrine, which is the burial place of the first Shia Imam.[xix] Shias travel to Najaf annually for the Arbaeen pilgrimage.[xx] The waiver includes strict operational guidelines, according to Iraqi and Western media.[xxi] CTP-ISW assessed on September 28 that Zaydi may view the limited waiver as a compromise between competing US and Iranian pressure.[xxii]

US and Partner Military Operations

Nothing significant to report.

Iranian Strike Campaign

• Assessed Iranian War Aims:
  • Secure international recognition of Iranian control over the Strait of Hormuz
  • Degrade the US ability and willingness to continue the war
  • Restore deterrence vis-à -vis the United States and its regional partners
  • Divide the United States and Israel from the Arab states

Iran could decide to expand attacks against regional infrastructure or shipping to try to alter the current situation in the war in which non-Iranian oil exports through the Strait of Hormuz are increasing and Iran is increasingly unable to sell oil.  The Wall Street Journal reported on September 28 that Middle Eastern oil exports reached nearly 13 million barrels per day in September, which is more than half of pre-war levels.[xxiii] The recent increase in oil exports is part of a larger trend of growing oil tanker and other commercial vessel traffic through the strait since late August despite Iranian efforts to restrict traffic.[xxiv] The Wall Street Journal also reported that Iranian crude oil loaded aboard vessels located outside the US blockade line has fallen from 29 million barrels in early September to approximately 15 million barrels and could run out by mid-October.[xxv] This report comes after US Treasury Secretary Scott Bessent stated on September 27 that Iran would deliver its remaining oil shipments to the People’s Republic of China (PRC) within two weeks, after which Iran would have “nothing left to trade for anything.”[xxvi] These reports highlight how Iran is facing a widening imbalance between increasing non-Iranian oil exports through the Strait of Hormuz and declining Iranian oil supplies outside the blockade line. Iranian Parliament Speaker Mohammad Bagher Ghalibaf warned on September 29 that “no one will sell oil” if Iran cannot sell its own and that “no infrastructure will be safe” if Iran’s “security” is not ensured.[xxvii] Ghalibaf’s remarks indicate that Iran may consider attacking regional energy infrastructure or shipping as its existing pressure on traffic through the strait produces diminishing returns. Iran has continued to attack shipping in the strait but at lower rates than it did earlier in the conflict. A likely Iranian projectile struck a vessel transiting the Strait of Hormuz on September 28 and caused a fire, for example.[xxviii]                   

US-Iran Negotiations

Iran’s deteriorating economic conditions appear to have driven officials from Iran’s pro-concessions camp to renew negotiations with the United States. Iranian, regional, and US sources assessed that Iran's recent meetings with mediators were in part due to Iran’s ongoing economic degradation, according to Reuters on September 29.[xxix] The US blockade on Iranian ports, ban on Iranian airlines, and increasing sanctions on Iran’s revenue networks have caused a foreign currency shortage that has increased inflation and led to the rial reaching an all-time low on September 29 (see graph below).[xxx] The blockade on Iranian ports and ban on Iranian airlines are also pushing Iran to increasingly rely on overland trade, which has caused long lines and delays near border crossings.[xxxi] Western media recently highlighted how some Iranian transportation workers have criticized the long border transit times and poor pay.[xxxii] Some government officials and members of the pro-concessions camp continue to acknowledge Iran’s worsening economic situation.[xxxiii] The Iranian government recently admitted that it is unable to increase salaries to compensate for increasing prices due to a lack of available resources, for example.[xxxiv]  These economic concerns appear to have driven Iranian negotiators, who are part of the pro-concessions camp, to engage in new talks with the United States.[xxxv] This camp has repeatedly advocated for reaching a deal with the United States to secure economic relief and thereby ensure domestic stability.[xxxvi] Recent rhetoric from hardline Iranian officials and media alongside continued Iranian attacks on shipping in the Strait of Hormuz reinforce CTP-ISW's assessment that the hardline IRGC faction controlling regime decision-making has not softened its position over key issues despite these economic conditions, however.[xxxvii]

                                                                      
Iranian Domestic Affairs

Nothing significant to report.

Lebanon

Nothing significant to report.

Iraq

See topline section.

Arabian Peninsula

Saudi leaders likely discussed the Houthi-Saudi conflict and prospects for international military support with US and Emirati officials on September 28 and 29.[xxxviii] Saudi Foreign Minister Faisal bin Farhan al Saud met with US Secretary of State Marco Rubio in Washington, DC, on September 28 before attending separate meetings with US Senate Intelligence and Armed Services Committee leaders on September 29.[xxxix] Saudi state media reported that Faisal and Rubio discussed strategic US-Saudi relations, protection for civilian maritime traffic, and safe passage through the Bab al Mandeb Strait and Strait of Hormuz.[xl] US government reports on the meeting differed from the Saudi official report, providing little detail on discussions concerning Yemen.[xli] Faisal and Rubio almost certainly discussed military developments in Yemen and the Houthi-Saudi conflict despite the differences in US and Saudi reports on the meeting’s contents, given that the Yemen conflict is currently Saudi Arabia’s primary security concern. Emirati state media separately reported on September 29 that Emirati Vice President and Deputy Prime Minister Mansour bin Zayed al Nahyan and a delegation of senior Emirati security officials met with Saudi Crown Prince Mohammed bin Salman in Riyadh to discuss regional developments.[xlii] Saudi officials have spoken with various international leaders in recent weeks to seek military support against the Houthis amid the group's offensive against the Saudi-backed Yemeni government and strike campaign against Saudi oil infrastructure.[xliii] Several Saudi partners, including the United States, the United Kingdom, and France, are providing chiefly defensive military support to Saudi Arabia, which poses a challenge to the Houthi strike campaign against Saudi Arabia.[xliv]

Emirati and Saudi leaders likely discussed potential security cooperation to confront the Houthis' threat to international maritime traffic, despite previous conflicts between Saudi-backed and Emirati-backed Yemeni forces in Yemen in late 2025 and early 2026.[xlv] The Houthis have increasingly attempted to assert formal authority and control over vessel passage through the Bab al Mandeb since Houthi forces captured the Red Sea coastal plain and islands in the southern Red Sea from Yemeni government-aligned forces between September 9 and 11.[xlvi] Iranian attempts to control the Strait of Hormuz and attacks on civilian vessels in the strait have imposed economic and political costs on the United Arab Emirates and other oil-exporting Gulf states, which Houthi control over the Bab al Mandeb would compound.[xlvii]

Iranian and Axis of Resistance advisers provided the Houthis with signals intelligence (SIGINT) and tactical planning before and during the Houthis' Red Sea coastal plain offensive between September 9 and 11, according to international media.[xlviii] Unspecified regional officials, a Houthi official, and an independent security analyst told the Associated Press on September 23 that Iranian Islamic Revolutionary Guards Corps (IRGC) advisers in Yemen assisted the Houthis with tactical planning, satellite imagery, and SIGINT before and during the coastal plain offensive.[xlix] A Yemeni journalist also reported on September 21 that Houthi, Hezbollah, and Iranian-backed Iraqi militia personnel developed and deployed vehicles carrying communications equipment to intercept radio transmissions from Yemeni government-aligned forces in Mokha and western Taiz Governorate during the offensive.[l] IRGC and other Axis of Resistance forces have also cooperated and coordinated with the Houthis to conduct attacks on Saudi Arabia during the ongoing regional conflict.[li] Regional officials told the Associated Press on September 9 that the Houthis helped Iraqi militias plan and conduct drone attacks on Saudi oil facilities in July 2026, for example.[lii]