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Red Sea Shipping Disruption: Bab al-Mandeb Selectively Constrained

Time window: Last 7 days · Audience: General analyst · Type: Situation report · DTG: 2026-09-13 01:07Z · Overall confidence: HIGH

BLUF

Likely, reported Houthi seizure of Mokha, Dhubab and Mayyun (Perim) will keep Bab al-Mandeb selectively constrained rather than fully closed over the next 0-14 days. Saudi vessels face the highest immediate exposure, while continuing Saudi-Houthi strikes and the 11 September East-West pipeline shutdown sustain energy and rerouting pressure.

Executive summary

Between 6 and 13 September, Houthi forces reportedly captured Mokha, Dhubab and Murad and established a presence on Mayyun, also known as Perim, near Bab al-Mandeb. The precise timing and nature of the Mayyun takeover remain disputed, but tracking data showing a 40 per cent rise in tankers anchoring near the strait indicates reduced willingness to transit. Houthi military statements exempt non-Saudi vessels while threatening Saudi shipping, and a Houthi-run ministry reported 73 ships transiting in two days, indicating continued passage rather than a confirmed full closure. Saudi-Houthi strikes continued on 13 September, including a projectile strike in Jazan, while Saudi Arabia shut the East-West pipeline on 11 September after a drone attack attributed variously to Iraq-based militias, the Houthis or Iran. The disruption is contributing to sustained energy and maritime pressure, although the wider Strait of Hormuz crisis remains a major confounding factor.

Change from previous assessment

Since 12 September, the assessment has shifted from reported Houthi movement onto Perim to likely established Houthi control of a wider set of positions around Bab al-Mandeb, although confidence remains medium because reporting still conflicts over the island's status and timing. The 40 per cent rise in tanker anchoring strengthens the judgement that access is selectively constrained rather than fully closed. Reporting on 13 September confirms continuing Saudi-Houthi strikes, including a projectile incident in Jazan, and the East-West pipeline shutdown is now a more prominent energy-risk indicator. No prior judgement is retired. The assessment of unlikely direct US strikes remains low-confidence because accounts of US and Saudi-Houthi diplomatic exchanges conflict.

Key judgments

1. Likely, Houthi forces have established effective control of Mokha, Dhubab, Murad and Mayyun (Perim) by 13 September, tightening their position at Bab al-Mandeb. Reports place the capture of Mokha on 9-10 September and the seizure or entry onto Mayyun (Perim) on 9-11 September. Reporting conflicts over whether government withdrawal or a forced takeover transferred the island, and over whether Houthi forces control the entire Yemeni Red Sea coast. Confidence is medium because multiple major-media reports corroborate the territorial advance, but the island's exact status and the timing of control remain contested. (Confidence: medium · ASSESSED)

• I&W: Confirm: independent reporting or imagery shows Houthi personnel, weapons or administrative activity on Mayyun (Perim) and at Dhubab throughout the next two weeks. (0-14 days)
• I&W: Break: Yemeni government forces return to Mayyun (Perim), Dhubab or Mokha, or multiple reliable reports attribute the apparent Houthi presence to a temporary withdrawal rather than control. (0-14 days)

2. Likely, commercial access through Bab al-Mandeb will remain selectively constrained rather than fully closed over the next 0-14 days. Tracking data shows a 40 per cent increase in tankers anchoring near the strait, while the Houthi-run Transport Ministry reported 73 ships transiting in two days and Yahya Saree said navigation was safe for all companies except Saudi vessels. These reports present competing pictures of disruption, and the transit figure is self-reported by the Houthi-run authorities. Confidence is medium. (Confidence: medium · ASSESSED)

• I&W: Confirm: tracking records another sustained rise in vessels anchoring near Bab al-Mandeb and a reduction in through-transits during the next two weeks. (0-14 days)
• I&W: Break: independently corroborated traffic remains steady while anchoring falls below the current 40 per cent increase and non-Saudi vessels continue routine passage. (0-14 days)

3. Very likely, Saudi vessels will remain the most exposed commercial category in the Red Sea and Bab al-Mandeb. Yahya Saree and other Houthi statements explicitly exempt non-Saudi shipping while declaring Saudi vessels subject to a blockade or ban. This is a policy declaration rather than proof of a completed maritime attack during the reporting period. Confidence is medium because several outlets repeat the same Houthi declaration, but independent confirmation of enforcement at sea is limited. (Confidence: medium · ASSESSED)

• I&W: Confirm: a Houthi statement or maritime incident identifies a Saudi-flagged, Saudi-owned or Saudi-linked vessel as attacked, detained or denied passage. (0-14 days)
• I&W: Break: the Houthi military rescinds the Saudi shipping ban and tracking records sustained Saudi vessel transits without reported attack, detention or prolonged anchoring. (0-14 days)

4. Very likely, Saudi-Houthi kinetic exchanges will continue to threaten maritime access and nearby energy infrastructure over the next 0-14 days. Houthi forces and Saudi Arabia were reported trading strikes at Bab al-Mandeb on 13 September, following Saudi airstrikes on Mokha and Houthi projectile attacks affecting Jazan, Khamis Mushait and other southern Saudi locations. The existence of continuing exchanges is well corroborated, although casualty figures and the characterisation of some targets remain disputed. Confidence is high. (Confidence: high · ASSESSED)

• I&W: Confirm: Saudi Civil Defence or Houthi military reporting records another projectile, drone or airstrike affecting Jazan, Najran, Mokha or Bab al-Mandeb. (0-14 days)
• I&W: Break: Saudi Arabia and the Houthis announce a bilateral cessation of strikes and no further incidents are reported for 14 consecutive days. (0-14 days)

5. Likely, energy-market pressure and maritime disruption will remain elevated over the next 1-3 months, but the Red Sea contribution cannot be separated from the wider Strait of Hormuz crisis. Saudi Arabia shut the East-West pipeline on 11 September after a drone attack, while about 5 million barrels per day had previously been rerouted through the pipeline to Yanbu. Brent briefly reached nearly US$110 per barrel before falling to US$104, and average US diesel prices reached US$6.06 per gallon. Responsibility for the pipeline attack remains contested between Iraq-based militias, the Houthis and Iran. Confidence is medium. (Confidence: medium · ASSESSED)

• I&W: Confirm: the East-West pipeline remains shut beyond 14 days, suffers another attack, or tanker anchoring near Bab al-Mandeb rises above the current 40 per cent increase. (0-14 days)
• I&W: Break: Saudi Arabia reopens the East-West pipeline, anchoring returns below the current increase and Brent remains below US$100 per barrel for four consecutive weeks. (1-3 months)

6. Unlikely, the US will conduct direct strikes against Houthi targets in Yemen over the next 0-14 days, while indirect US support to Saudi Arabia is likely to continue. The White House has described a policy of ensuring freedom of navigation while empowering regional partners, and reporting places more than 100 US military advisers in Saudi Arabia supporting intelligence efforts. Accounts of senior-level diplomacy conflict: some reporting says Mohammed bin Salman sought US strikes and Donald Trump declined, while Trump says the Houthis asked Washington not to intervene. Confidence is low because the diplomatic accounts conflict and some reporting is based on anonymous sources. (Confidence: low · ASSESSED)

• I&W: Confirm: the White House or US Department of Defence announces direct US strikes against Houthi targets in Yemen. (0-14 days)
• I&W: Break: Washington reiterates the regional-partner approach while Saudi Arabia reports continued US intelligence, targeting or advisory support without direct US strikes. (0-14 days)

Outlook & scenarios

Selective constraint persists (60%)

Likely, Houthi forces retain Mokha, Dhubab and Mayyun (Perim), continue threatening Saudi vessels and permit at least some non-Saudi commercial traffic through Bab al-Mandeb. Tanker anchoring remains elevated, but the strait does not close completely.

Sharp disruption after escalation (25%)

Unlikely but high impact, a Houthi attack on a non-Saudi commercial vessel or a wider Saudi air campaign prompts major carriers to suspend Bab al-Mandeb transits. Anchoring rises sharply, rerouting around Africa expands and energy prices move higher.

Managed de-escalation (10%)

Unlikely, US-Houthi discussions and the planned Iran-Gulf meeting in Oman produce reciprocal restraint. Houthi statements preserve the Saudi exception initially, but the frequency of Saudi-Houthi strikes falls and commercial traffic gradually increases.

Regional escalation involving Iraq and Iran (5%)

Unlikely and high impact, further attacks on Saudi energy infrastructure are attributed to Iran or Iraq-based militias, prompting Saudi or US military action beyond Yemen. The resulting cross-theatre escalation places both Bab al-Mandeb and the wider Gulf shipping system under severe pressure.

Recommendations

1. Maintain a 24-hour shipping watch that separates through-transits, vessels anchoring near Bab al-Mandeb and vessels rerouting around Africa. Record daily changes against the current 40 per cent increase in tanker anchoring.
2. Treat Saudi vessels as a separate risk category in all maritime reporting. Track Houthi statements, vessel ownership and flag, reported delays, and any incident involving a Saudi-linked ship.
3. Require two-source confirmation before assessing Mayyun (Perim), Dhubab or Mokha as fully controlled by the Houthis. Distinguish physical presence, government withdrawal and durable administrative control.
4. Track the East-West pipeline's operating status, Yanbu-bound flows, Brent crude and US diesel prices as separate indicators. Do not attribute market movements solely to Bab al-Mandeb while Strait of Hormuz disruption remains active.
5. Maintain a dedicated US involvement tracker distinguishing direct strikes, intelligence sharing, targeting assistance, adviser deployments and diplomatic statements. Treat conflicting accounts of requests by Mohammed bin Salman and the Houthis as unresolved.
6. Include the humanitarian operating picture in maritime updates, particularly the displacement of more than 46,000 people and the detention of 73 UN staff, because further territorial consolidation around Yemen's Red Sea coast can constrain aid access.

Confidence & uncertainty

Overall confidence is high because the core developments are corroborated by multiple high-reliability major-media, official government, UN and multilateral reports. Houthi territorial gains, continuing Saudi-Houthi strikes, tanker anchoring, the East-West pipeline shutdown and oil-price movement each have more than one reporting stream. The main uncertainties concern the precise status and date of Mayyun (Perim), responsibility for the pipeline attack, actual transit volumes, casualty figures and the direction of recent US diplomatic exchanges. These uncertainties affect attribution and severity, but not the assessment that Bab al-Mandeb access is under pressure.

Alternative analysis (red cell)

The territorial reporting may indicate a rapid Houthi advance and temporary entry into key positions, but it does not yet demonstrate effective control of Mokha, Dhubab, Murad, and Mayyun as a consolidated territorial bloc. The strongest evidence is either a single broad account or reports of withdrawal and subsequent entry, while the timing and manner of the Mayyun transfer remain disputed. Accordingly, the evidence supports an assessment of reported Houthi presence and increased pressure at Bab al-Mandeb, not established control of all named sites.

Intelligence gaps

• [EEI 1.1 · PARTIAL] Incidents of hostile action against commercial vessels: vessel name/IMO, position (lat/long), time/date, observable damage or casualties, and weapon type reported (missile, drone, small-arms, explosive-laden boat). Recommended collection: maritime/AIS
• [EEI 1.2 · PARTIAL] Public Houthi claims of attacks or warnings tied to specific dates/routes, including social-media posts, official statements, and timing relative to merchant transits. Recommended collection: open-source/social_media
• [EEI 1.3 · UNCOVERED] Unusual Houthi force posture indicators along Yemen’s Red Sea coast: movement or concentration of small boats, visible coastal missile/rocket emplacements, or logistics buildup at known launch sites (locations, timestamps). Recommended collection: imagery/satellite
• [EEI 1.4 · UNCOVERED] Intercepts or communications indicating orders, targeting lists, or intent to strike merchant shipping (messages referencing specific vessel classes, companies, or chokepoints). Recommended collection: signals/communications
• [EEI 2.1 · UNCOVERED] Reports or visual confirmation of floating or moored mines and debris fields in shipping lanes or approaches to Bab-el-Mandeb, with geolocation and time. Recommended collection: imagery/satellite
• [EEI 2.2 · UNCOVERED] Detection of mine-laying activity: small vessels loitering in lane approaches, unexpected AIS track patterns consistent with mine deployment, or salvage/mining vessels operating in the area. Recommended collection: maritime/AIS
• [EEI 2.3 · UNCOVERED] Hydrographic notices, naval warnings, or port authority advisories closing lanes or imposing route restrictions (text of Notice to Mariners, issuing agency, effective times/areas). Recommended collection: naval/port_authority
• [EEI 2.4 · UNCOVERED] Naval or commercial reports of mine-countermeasure operations or confirmed mine removal events (location, time, platforms involved). Recommended collection: naval/intelligence
• [EEI 3.1 · PARTIAL] Movements and presence of foreign warships and support vessels: names/classes, task group compositions, patrol areas and timelines, and whether vessels are conducting escort or interdiction operations. Recommended collection: naval/intelligence
• [EEI 3.2 · UNCOVERED] Official announcements or directives from states/coalitions regarding convoys, armed escorts, protected corridor establishment, or changes to rules of engagement for merchant protection. Recommended collection: diplomatic/public_affairs
• [EEI 3.3 · UNCOVERED] Recorded interactions between naval forces and vessels in the corridor (hailings, boardings, warnings, defensive strikes), including timestamps and outcomes. Recommended collection: maritime/AIS
• [EEI 3.4 · PARTIAL] Planned or ongoing multinational exercises, air ISR sorties, or logistics moves that increase or decrease naval capacity in the area (exercise name, participating units, dates, locations). Recommended collection: open-source/military_reporting
• [EEI 4.2 · UNCOVERED] War-risk and hull insurance coverage changes: issuance refusals, premium increases for Red Sea transits, or explicit route exclusions by underwriters (policy notices or market rate data with dates). Recommended collection: commercial/insurance_data
• [EEI 4.3 · UNCOVERED] Freight and charter market signals tied to the corridor: spot rates for container, tanker, and dry bulk routes affected by Red Sea disruptions, and reported port congestion or turnaround-time increases at nearby hubs. Recommended collection: commercial/market_data
• [EEI 4.4 · PARTIAL] Incidents of cargo denial or diversion for critical goods (crude oil, refined products, LNG, high-value container cargo) including vessel IDs, cargo type, reroute/turnback actions, and economic impact estimates where available. Recommended collection: maritime/AIS

Cited sources

[1] Bhaskar English (Dainik Bhaskar) · After Hormuz, another oil route faces crisis: Houthis seize control of Bab al-Mandeb; ships from all except.. (B) · Fri Sep 11 2026 09:48:32 GMT+0000 (Coordinated Universal Time) · sha256:73f8eeb0f1a4 [2] Euronews · Houthis seize key island in Bab el-Mandeb, take control of the strait (A) · Fri Sep 11 2026 22:08:14 GMT+0000 (Coordinated Universal Time) · sha256:ddd285f40807 [3] USA Today · Iran, Houthis block 2 key global shipping routes, straining the global economy (A) · Sat Sep 12 2026 01:51:45 GMT+0000 (Coordinated Universal Time) · sha256:efbcf1ec4981 [4] Arkansas Democrat-Gazette (arkansasonline.com) · Houthis take Red Sea island near key strait (C) · Sat Sep 12 2026 08:22:00 GMT+0000 (Coordinated Universal Time) · sha256:769a6f98bf49 [5] Alaraby Misr (Arabi 21 TV – Egypt) via Facebook · وسط مخاوف من استهداف الملاحة في باب المندب. وزارة النقل في حكومة الحوثيين تشير إلى عبور 73 سفينة خلال اليومين الماضيين | التلفزيون العربي – مصر (E) · sha256:efe8e17b09dc [6] Al Jazeera · Iran war live: Saudi Arabia and Houthis trade strikes over Bab al-Mandeb (A) · Sun Sep 13 2026 00:00:40 GMT+0000 (Coordinated Universal Time) · sha256:d802f39fc255 [7] BBC · Lightning Houthi advance in Yemen may bring dangerous new dimension to Iran war (A) · Fri Sep 11 2026 19:44:58 GMT+0000 (Coordinated Universal Time) · sha256:34c6568e370a [8] BBC · How global trade and oil prices could be hit by Houthi advance (A) · Fri Sep 11 2026 16:13:39 GMT+0000 (Coordinated Universal Time) · sha256:9ae3ec3bb28e [9] Al Jazeera · Houthi projectile wounds two, damages mosque in Jazan region, Saudi says (A) · Sun Sep 13 2026 00:24:29 GMT+0000 (Coordinated Universal Time) · sha256:3426fb99b1bf [10] DT Next (dtnext.in) · Iraq races to contain fallout after local Iran-backed militias accused of attacking Saudi pipeline (B) · Sat Sep 12 2026 12:18:31 GMT+0000 (Coordinated Universal Time) · sha256:e23ce5a91d08 [11] The Associated Press (via ABC7 Chicago) · Attack on key Saudi pipeline is blamed on Iran-backed militias in Iraq (A) · Sat Sep 12 2026 12:25:00 GMT+0000 (Coordinated Universal Time) · sha256:22ec13c1080f [12] KESQ (republishing CNN Wire) · Trump says Iran likely responsible for attack that shut vital Saudi oil pipeline (C) · Sat Sep 12 2026 15:50:56 GMT+0000 (Coordinated Universal Time) · sha256:ea8ce31e711f [13] CBC News (with reporting from The Associated Press) · Iraq scrambles to address fallout from alleged militia attack on Saudi oil pipeline (A) · Sat Sep 12 2026 12:40:20 GMT+0000 (Coordinated Universal Time) · sha256:7506dd157ad5 [14] The Associated Press (via CP24) · Iraq races to contain fallout after local Iran-backed militias accused of attacking Saudi pipeline (A) · Sat Sep 12 2026 12:03:55 GMT+0000 (Coordinated Universal Time) · sha256:4d3e54405998

Source content hashes were computed at collection time; the cited text is preserved unmodified for the life of this product.

Red cell review: PARTIAL DISSENT

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