Bottom Line
Commercial traffic through the Strait of Hormuz is very likely to remain severely constrained through 20 September 2026 at 01:20 UTC, with an estimated 82 per cent probability and moderate confidence. Severe constraint is defined here as commodity-vessel throughput below 50 per cent of the specified pre-conflict baseline for three consecutive days. The estimate comprises a 67 per cent probability of severe constraint without a complete 48-hour closure and a 15 per cent probability of a closure lasting at least 48 hours.
The four commodity vessels recorded by Kpler on 15 September, the reported 18 million barrels transiting on one day and the 11 million barrel seven-day average attributed to US Energy Secretary Chris Wright are not interchangeable measures. They use different time periods, vessel categories and denominators. The IMO's verification of 80 attacks around Hormuz and at least 22 seafarer deaths supports the disruption assessment, but the source record does not establish the precise volume still moving.
The CrisisBrief Index is 78 out of 100, labelled SEVERE. The score is a comparative daily indicator rather than an objective measure of world conditions. It uses a fixed weighting of conflict 35 per cent, maritime trade 25 per cent, energy 20 per cent and political risk 20 per cent. Today's components are conflict 84, maritime trade 84, energy 79 and political risk 58, producing a weighted score of 78 after rounding.
Key Developments
1. Hormuz and Saudi-linked shipping
Reported fact: Kpler recorded four commodity vessels transiting the Strait of Hormuz on 15 September. The source material gives a pre-conflict reference of roughly 125 large commercial vessels per day. The IMO has verified 80 attacks around Hormuz and at least 22 seafarer deaths since 28 February. Chris Wright reported 18 million barrels of crude and products transiting on one day and an 11 million barrel seven-day average.
Assessment: Severe Hormuz constraint is very likely through 20 01 September:20 UTC, at 82 per cent and moderate confidence. The evidence converges on serious disruption, but not on a complete closure or a reliable single flow percentage. A 15 per cent closure estimate is therefore separate from, and included within, the 82 per cent severe-constraint estimate.
Reported fact: Reporting places Ansar Allah forces around Mokha, Dhu Bab, Perim Island and the Greater and Lesser Hanish islands. Kpler recorded two Saudi vessels transiting the Red Sea from 7 September. The source material does not specify whether the count is based on Saudi flag, ownership, destination or another measure. Saudi Arabia has suspended Yanbu loadings and the East-West Pipeline remains offline.
Assessment: Saudi-linked shipping and crude logistics are likely to remain impaired through 2 October, at 70 to 80 per cent and moderate confidence. The reduction in Saudi-linked traffic is reported, but the proportion caused by Ansar Allah activity is not established. Alternative explanations include the pipeline outage, Saudi risk avoidance, changes in voyage destination and broader Red Sea insecurity. Attribution of the pipeline attack remains contested between accounts identifying Ansar Allah and accounts identifying drone activity originating from Iraq.
2. Russia-Ukraine strike cycle
Reported fact: Ukraine's air force reported 157 Shahed and Parody drones and additional missiles in the 17 September attack, claiming 131 targets destroyed or suppressed by 08:00 UTC. These are Ukrainian military figures and are not independently verified. Kyiv, Odesa, Zaporizhzhia and Berestyn reported damage and casualties. Ukraine also reported damage to the Slavneft-YANOS refinery in Yaroslavl and strikes on aircraft and helicopters at Rostov-Central.
Assessment: Another high-volume Russian strike package by 21 September is very likely, at 75 to 85 per cent and high confidence. Ukraine is likely to continue long-range attacks against Russian energy and military infrastructure through 17 October, at 60 to 70 per cent and moderate confidence. A substantive Russia-Ukraine ceasefire by 18 October is very unlikely, below 15 per cent and high confidence. The 17 September strike and continuing reciprocal attacks are inconsistent with a functioning, jointly monitored energy-target pause.
Ukraine's 3rd Army Corps has confirmed Operation Vivaldi north of Lyman. Ukrainian forces claim territorial gains and Russian pro-war channels acknowledge movement towards the Zherebets River, but the extent of Ukrainian control remains disputed. Ukraine is likely to retain a local initiative in the Lyman area through 2 October, at about 60 per cent and moderate confidence. The operation does not yet establish a wider battlefield reversal.
3. China, Taiwan and the South China Sea
Reported fact: China Coast Guard pairs have conducted recurring patrols east of Taiwan, PLA aircraft and vessels continue activity across the Taiwan Strait median line, and China has issued navigation closures for training in the South China Sea. The revised National Defense Mobilization Law is scheduled to enter force on 1 October and expands the legal framework for access to civilian ships, aircraft and land.
Assessment: Chinese coercive maritime activity around Taiwan and the South China Sea is very likely to continue through 1 October, at 80 to 90 per cent and moderate confidence. Military action against Taiwan solely because the revised law enters force is unlikely through 18 December, below 20 per cent and low confidence. The judgement would change if Beijing issues a Taiwan-linked mobilisation order, requisitions commercial shipping or aircraft, conducts sustained invasion-scale exercises or moves large numbers of civilian vessels under military control.
4. Europe and Russia-linked hybrid activity
Reported fact: The European Parliament adopted a non-binding resolution by 470 votes to 129, with 62 abstentions, calling for stronger sanctions and emergency consultations over hybrid activity. European authorities have reported drone incidents, suspected sabotage, arson planning and intimidation networks linked by some investigations to Russian intelligence services. Attribution remains unresolved in several cases.
Assessment: Russia is very likely to sustain deniable hybrid activity against European targets through 17 December, at 75 to 85 per cent and moderate confidence. A dangerous incident near NATO territory is likely, at 55 to 65 per cent, while open Russia-NATO kinetic conflict remains unlikely, below 15 per cent. A confirmed deliberate attack causing casualties on NATO territory would break the current assessment.
5. Humanitarian pressure
Reported fact: UNICEF reports more than 57,000 children displaced in Yemen during two weeks, disruption at 26 supported health facilities and closure or suspension of 243 schools affecting more than 137,000 students. OCHA reports that 1.98 million people in Gaza require shelter and non-food assistance and that roughly nine in ten people are internally displaced. Blue Nile recorded 99,277 displaced people between January and August, according to IOM-linked reporting.
Assessment: Humanitarian conditions in Yemen, Gaza and Sudan are very likely to worsen through 18 December, at 70 to 85 per cent and high confidence. The judgement rests on UN, UNICEF, OCHA and IOM reporting across several locations. The exact Yemen displacement total remains uncertain because the reported figures cover different periods and geographic areas.
6. Sahel violence
Reported fact: ACLED-referenced reporting records 2,145 incidents involving Islamist militant violence in Mali, Burkina Faso and Niger by 16 September 2026, compared with 2,845 during all of 2025. JNIM has claimed more than 130 attacks in Burkina Faso during 2026 and at least 17 in Niger, while UN reporting assesses Islamic State in the Greater Sahara as more active than JNIM in Niger.
Assessment: Violence involving JNIM and Islamic State-linked groups is very likely to exceed the 2025 incident total by the end of 2026, at 70 to 80 per cent and moderate confidence. The figures are reported through major media citing ACLED and are not independently corroborated at incident level. The assessment concerns incident volume, not the less reliable projection of more than 9,000 security-related deaths.
Analysis
Analytic continuity
The current assessment is broadly consistent with the 17 September briefing, but the evidence changes confidence at the margins.
| Prior judgement | Current disposition | Current assessment and reason |
|---|---|---|
| Severe Hormuz constraint through 20 September at 82 per cent | Carried forward unchanged | The four-vessel Kpler observation supports severe disruption. The 18 million-barrel day and 11 million-barrel weekly average prevent a higher estimate and keep confidence moderate. |
| Complete Hormuz closure for 48 hours at 15 per cent | Carried forward unchanged | Some movement continues and no source verifies 48 consecutive hours without commercial transit. Mine-laying, a fatal maritime encounter or a major tanker attack would raise the estimate. |
| Severe constraint without closure at 67 per cent | Carried forward unchanged | This remains the mutually exclusive residual severe-constraint outcome after the 15 per cent closure estimate is removed from the 82 per cent total. |
| Material reopening to at least 50 per cent before 20 September at 18 per cent | Carried forward unchanged | Reported oil volumes do not equal the defined commodity-vessel measure. No three-day recovery to at least 50 per cent is reported. |
| Saudi East-West Pipeline impairment through early October | Carried forward, duration confidence moderate | The outage and suspended Yanbu loadings remain reported. Chris Wright's days-long restoration estimate conflicts with regional and trade reporting that supports an outage lasting weeks. |
| Ansar Allah pressure on Saudi-linked shipping through 1 October | Carried forward, moderate confidence | Reported positions and reduced Saudi-linked traffic support continuation, but the transit definition and causation remain unresolved. |
| Brent crude and tanker freight costs elevated for 14 days | Carried forward, moderate confidence | Maritime disruption and pipeline impairment support persistence above pre-conflict levels, but the collection does not support a single price threshold. |
| Russian attacks against Ukrainian cities and infrastructure through 20 September | Carried forward, high confidence | The 17 September multi-platform attack and continuing damage reports reinforce the prior judgement. |
| Ukrainian long-range attacks against Russian energy and military assets through 17 October | Carried forward, moderate confidence | Yaroslavl and Rostov-Central reporting supports continuation, but operational effects remain partly unverified. |
| Verified bilateral halt covering energy strikes unlikely by 1 October | Carried forward, high confidence | Reciprocal strikes continue and no jointly monitored mechanism is reported. |
| Dangerous Russia-NATO encounter by 17 October | Revised in horizon only | The estimate is extended to 17 December at 55 to 65 per cent because drone and maritime incidents continue, while open Russia-NATO war remains unlikely. |
| Sahel violence above the 2025 annual incident total by end-2026 | Carried forward, moderate confidence | ACLED-referenced reporting records 2,145 incidents by 16 September against 2,845 in all of 2025 and projects a higher year-end total. |
| Durable SAF-RSF ceasefire unlikely through 17 October | Carried forward, moderate confidence | Current reporting continues to show fighting in Kordofan, Blue Nile and Darfur and no verified durable ceasefire. |
Stakeholder implications
US CENTCOM: Continued low Hormuz throughput and the IMO incident record imply persistent force-protection and maritime deconfliction demands. A verified Ansar Allah attack on a US vessel or US personnel, or new Iranian mine-laying evidence, would invalidate the current assessment that direct US strikes in Yemen remain unlikely.
Saudi Aramco and Saudi authorities: The unresolved East-West Pipeline repair timeline leaves the volume and route of Saudi crude exports uncertain. Verified pumping-station repairs and resumed Yanbu loadings would support rapid partial recovery. No flow evidence by 25 September would support a weeks-long outage and continued reliance on routes exposed to Hormuz and Red Sea disruption.
Commercial carriers and marine insurers: Saudi-linked shipping faces a narrower and more direct threat from Ansar Allah than non-Saudi traffic, but the absence of a clear targeting boundary limits the practical protection offered by Ansar Allah statements. A named-vessel attack, a new navigation closure or a sharp war-risk premium increase would support reversal of the current Suez service recovery.
European carriers and importers: Suez recovery reduces some Asia-Europe container exposure, but it does not restore Gulf crude flows or remove the risk of renewed Cape routing. Carrier schedule reversals and higher insurance premiums are more useful indicators of commercial disruption than a single daily Hormuz oil-volume report.
NATO commands and European governments: Repeated Russian-linked drone and maritime incidents support continued air and maritime deconfliction. A confirmed airspace violation causing damage or casualties would carry greater escalation significance than an unattributed drone sighting and would raise the risk of an accidental Russia-NATO exchange.
Taiwan, Japan and US Indo-Pacific commands: The 1 October Chinese mobilisation-law change is an important legal milestone but not an operational mobilisation order. Requisition of civilian shipping, unusual PLA logistics or a Taiwan-specific exercise would be the indicators that materially change the current low-confidence assessment of near-term Chinese military action.
Source quality and limitations
The collection is weighted towards high-reliability reporting, including UN agencies, the IMO, UNICEF, OCHA, IOM, Kpler, major wire services and official military reporting. Other material consists of official party claims, militant statements, local reporting, satellite interpretation, trade publications and anonymous diplomatic accounts. The Ukrainian 157-drone count, Ansar Allah territorial and attack claims, Saudi attribution of the Mecca-area drone and some diplomatic accounts are not independently corroborated. These limitations reduce confidence in attribution, territorial control and operational effect, but they do not remove the evidence for maritime disruption, humanitarian deterioration or continued Russian strike activity.
Indicators & Warnings
- Iranian maritime warning or mine-laying preparation: Watch for new IMO, JMIC, UKMTO or Iranian exclusion zones, mine-laying evidence or unusual small-boat deployments. Horizon: 24 to 72 hours. Three days without such evidence lowers confidence in imminent full closure but does not alter the severe-constraint estimate.
- Hormuz throughput: Watch for Kpler or Clarksons reporting below 50 per cent of the defined baseline for three consecutive days, or at least 50 per cent for three consecutive days. Horizon: 24 to 96 hours. The first outcome confirms severe constraint; the second lowers confidence and supports the reopening scenario.
- Named-vessel incident: Watch for a confirmed projectile impact, mine strike, boarding, detention, casualty or forced diversion involving a named vessel. Horizon: 24 to 72 hours. A new incident raises the closure estimate unless evidence shows it was isolated and transit continues.
- East-West Pipeline: Watch for Saudi Aramco, satellite or Yanbu port evidence of pumping-station repairs and resumed loading. Horizon: initial evidence by 21 September, duration update by 25 September and 2 October. Flow by 21 September supports partial recovery; no flow by 25 September supports a prolonged outage.
- Ansar Allah targeting change: Watch for public targeting of US or Israeli vessels, a verified strike on Saudi-linked shipping or a new attack on Yanbu. Horizon: 24 hours to 14 days. A US or Israeli vessel attack raises the estimate for direct US action in Yemen.
- Carrier and insurer behaviour: Watch for war-risk premium increases or reversal of Suez services by Maersk, Hapag-Lloyd, COSCO, MSC or CMA CGM. Horizon: 24 hours to 14 days. Two major carriers returning to the Cape route within seven days supports renewed broad Red Sea disruption.
- Russian strike cycle: Watch for another package exceeding 100 drones or involving ballistic and cruise missiles by 21 September. Horizon: 24 to 72 hours. A comparable package confirms continuation; seven days without one lowers the near-term tempo estimate but does not establish a ceasefire.
- Russia-NATO encounter: Watch for a confirmed Russian or Belarusian airspace violation, NATO interception or a Russian warship incident causing damage or casualties. Horizon: 24 hours to 14 days, with the wider forecast through 17 December. Damage or casualties raise the dangerous-encounter estimate.
- Operation Vivaldi: Watch for geolocated Ukrainian control beyond the current Lyman positions, Russian counterattacks across the Zherebets River or Ukrainian withdrawal. Horizon: 72 hours to 14 days. Seven days of confirmed Ukrainian control would support a broader local initiative.
- China-Taiwan mobilisation: Watch for a Taiwan-linked order, requisition of civilian shipping or aircraft, unusual PLA logistics or large-scale exercises after 1 October. Horizon: 1 October to 18 December. Any Taiwan-specific requisition raises the military-action estimate above the current below-20-per-cent level.
Alternatives
The Hormuz alternatives are mutually exclusive and sum to 100 per cent: severe constraint without a complete closure, 67 per cent; closure for at least 48 hours, 15 per cent; and reopening to at least 50 per cent of the specified baseline, 18 per cent. The Ansar Allah direct-US-action scenario is a conditional escalation overlay and is not added to that distribution.
The main non-Hormuz alternative is a reduction in Russia's strike tempo without a substantive ceasefire, assessed at 25 per cent through 21 September. Ukraine's Operation Vivaldi is more likely to remain a localised action than produce a wider battlefield reversal, assessed at 65 per cent through 2 October. China is assessed at 80 per cent to maintain coercive pressure without initiating military action against Taiwan through 18 December. A reversal of Suez routing after a new Red Sea incident is assessed at 25 per cent through 2 October.
Outlook
Severe Hormuz constraint is very likely through 20 01 September:20 UTC, at 82 per cent and moderate confidence. Ansar Allah pressure on Saudi-linked shipping and energy infrastructure is likely through 2 October, at 70 to 80 per cent and moderate confidence. Direct US strikes against Ansar Allah remain unlikely over the next 14 days, but a verified attack on a US vessel, US personnel or a major Saudi energy facility would materially change that judgement.
Russia is very likely to conduct another high-volume attack against Ukraine by 21 September, at 75 to 85 per cent and high confidence. A substantive Russia-Ukraine ceasefire by 18 October is very unlikely, below 15 per cent and high confidence. China is very likely to continue maritime pressure around Taiwan and the South China Sea through 1 October, while military action against Taiwan solely because the revised mobilisation law enters force remains unlikely through 18 December and low confidence.
The CBX remains in the SEVERE band because conflict intensity, maritime disruption and energy risk are all high, while political risk is elevated rather than severe. The index would move towards the CRITICAL range if Hormuz traffic ceased for 48 hours, a US-Iran maritime incident caused mass casualties, Ansar Allah struck a US vessel, Russia conducted a deliberate lethal attack on NATO territory or China issued a Taiwan-linked mobilisation order.