Iran Update: September 27, 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 daily updates to provide analysis on developments in the Middle East over the past 24-hour period.

Note: CTP-ISW will begin publishing abbreviated weekend updates covering the Houthi-Saudi conflict beginning on September 26, 2026.

Key Takeaways:

• Saudi and Yemeni government-aligned forces targeted Houthi forces positioned east of Taiz City on September 27, likely to disrupt the Houthis’ ability to sustain operations east of the city. Yemeni government-aligned forces also continue to engage Houthi forces in mountainous terrain overlooking the Bab al Mandeb.
• The United Kingdom arrested five men near Royal Air Force (RAF) Fairford on suspicion of making preparations for a terrorist attack involving explosives. Sources familiar with the investigation told the Telegraph that Iranian agents likely played a direct role in the suspected plot, but local authorities have not yet released the detainees’ identities.
• Iran has continued its efforts to drive up global oil prices in order to compel the United States to accept Iranian demands, including recognized Iranian control over the Strait of Hormuz. The Islamic Revolutionary Guards Corps (IRGC) Navy claimed that Iran has targeted 19 vessels that have attempted to transit the strait since September 25, though Iranian media provided no evidence to substantiate these claims.

Toplines

Saudi and Yemeni government-aligned forces continue to strike Houthi targets along frontlines in southwestern Yemen. The Yemeni military announced on September 27 that it has conducted 756 “operations,” including airstrikes, targeting Houthi reinforcements and military equipment across multiple fronts in Yemen since September 24.[i] The Yemeni military claimed that its operations killed four Iranian drone and missile experts in Taiz Governorate, which exemplifies the direct role that the Islamic Revolutionary Guards Corps (IRGC) is playing in support of Houthi operations in Yemen.[ii]

Saudi and Yemeni government-aligned forces targeted Houthi forces positioned east of Taiz City on September 27, likely to disrupt the Houthis’ ability to sustain operations east of the city. The Yemeni government's military said on September 26 that it struck several Houthi targets in Taiz Governorate, including the Houthi Istiqbal camp in Mawiyah, east of Taiz.[iii] A Marib-based anti-Houthi journalist also reported airstrikes on warehouses east of Taiz City that reportedly supplied food to Houthi forces based in the area.[iv] The same account also claimed that a strike on a newly-established Houthi camp near al Hawban, southwest of Taiz City, killed Houthi official Nour al Din al Marani.[v] Marani held multiple positions and responsibilities before his reported death, including as Taiz Governorate’s Deputy Governor for Defense and Security Affairs and the Houthis’ Fourth Military Region Assistant Commander. Marani was reportedly responsible for Houthi drone operations in Taiz, Lahij, and Dhaleh governorates.[vi] The Houthis reportedly moved reinforcements from Ibb Governorate toward al Hawban in mid-September 2026.[vii] Houthi forces positioned in al Hawban and east of Taiz City could support future Houthi operations to seize Taiz City. The Houthis are currently threatening the primary ground line of communication (GLOC) that connects Taiz City to Aden City.[viii] Houthi control over the Taiz-Aden GLOC would effectively encircle Yemeni government forces in Taiz City and set conditions for the Houthis to seize the city.

Yemeni government-aligned forces also continue to engage Houthi forces in mountainous terrain overlooking the Bab al Mandeb. The Southern Giants Brigades conducted a drone strike targeting Houthi forces and vehicles along the Jabal Kahbub front on September 27.[ix] A Yemeni government-affiliated news aggregator cited unconfirmed reports on September 26 that fighting near Jabal Kahbub killed a Houthi naval commander.[x] Jabal Kahbub is approximately 30 kilometers north of Houthi positions by the Bab al Mandab Strait. Geolocated footage posted on September 26 separately shows Yemeni government-aligned forces and southern tribal fighters engaging Houthi forces near Jabal Numan.[xi] Houthi forces have engaged Yemeni government forces near Jabal Numan since at least September 21 in an attempt to advance eastward into western Taiz Governorate.[xii]

The United Kingdom arrested five men near Royal Air Force (RAF) Fairford on suspicion of making preparations for a terrorist attack involving explosives.[xiii] Sources familiar with the investigation told the Telegraph that Iranian agents likely played a direct role in the suspected plot, but local authorities have not yet released the detainees’ identities.[xiv] RAF Fairford serves as a forward operating base for the US Air Force Global Strike Command.[xv] The United Kingdom previously authorized the United States to use US bombers based at the Fairford base to strike Iranian missile sites that targeted ships in the Strait of Hormuz.[xvi] Iran has repeatedly threatened to attack bases that either support US operations against Iran or host US forces or equipment.[xvii] Local sources told CNN that authorities have increased security at the base in recent weeks.[xviii]

Iran has continued its efforts to drive up global oil prices in order to compel the United States to accept Iranian demands, including recognized Iranian control over the Strait of Hormuz. The IRGC Navy claimed on September 27 that Iran has targeted 19 vessels that have attempted to transit the strait since September 25, including seven vessels overnight on September 26 and 27.[xix] Iranian media provided no evidence to substantiate these claims. The UK Maritime Trade Operations has not reported any attacks against vessels in the strait since September 23 but has reported continued Iranian intimidation of commercial shipping.[xx] The Iranian claims, regardless of their veracity, likely seek to create an informational effect that increases shipping companies’ risk perceptions of transiting the strait without Iranian permission. These claims come as US efforts to restore freedom of navigation continue to challenge Iran's ability to enforce control over the strait. US Treasury Secretary Scott Bessent stated on September 27 that between 15 and 22 million barrels of oil currently pass through the strait daily, compared to the 20 million barrels of oil that passed through the strait daily before the war.[xxi]

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

Nothing significant to report.

US-Iran Negotiations

Nothing significant to report.
Iranian Domestic Affairs

Nothing significant to report.
Lebanon

Nothing significant to report.

Iraq
Nothing significant to report.

Arabian Peninsula

Nothing significant to report.