Houthi embargo on Saudi shipping and attacks at Bab el-Mandeb

Name: Measured effect: Houthi embargo on Saudi shipping and attacks at Bab el-Mandeb
Creator: World Freight Monitor
License: https://creativecommons.org/licenses/by/4.0/

Houthi embargo on Saudi shipping and attacks at Bab el-Mandeb. The disruption ran from 2026-07-20 (20 July 2026), and is ongoing, affecting Bab el-Mandeb Strait. Bab el-Mandeb Strait averaged 8.3 transits per day during the event window against an expected 13.7 (-39.7%). Bab el-Mandeb Strait averaged 27.4 transits per day during the event window against an expected 36.3 (-24.4%).

Follow this disruption day by day

Key facts

Started: 2026-07-20 (20 July 2026)
Ended: Not ended
Status: ongoing
Type: Security incident
Severity: 3 Significant
Scope: chokepoint
Chokepoints: Bab el-Mandeb Strait
Ports: None
Lanes: None
Countries: Yemen, Saudi Arabia
Confidence: medium: Two outlets agree on the embargo and the warnings, but no official maritime authority notice could be retrieved, so all narrative sources are press. The attack on the Tihamah rests on statements by the Yemeni government. Casualties are left out because no official source was read. The transit decline is measured in PortWatch but its cause is not established by the data.
First reported: 2026-07-20 (20 July 2026)

Severity basis: A restriction at a chokepoint. Measured on top of the Red Sea diversion (wfm-effect-1.1): PortWatch tanker transits at Bab el-Mandeb 8.5 a day from 2026-07-20 to 2026-09-13 against 13.7 expected, down 38 percent; total transits down 23 percent, below the 25 percent needed for level 4.

What happened

On 2026-07-20 (20 July 2026) Yemen's Houthis declared a maritime embargo on Saudi Arabia, prohibiting vessels loading or discharging at Saudi ports, days after an attack on Sanaa airport. Two days later a US Navy-led maritime information centre warned that the group had positioned missiles and drones near the Bab el-Mandeb Strait, and ship trackers saw four tankers with Saudi cargo turn back. On 2026-08-11 the Egyptian-owned Tihamah was hit in the strait, in what Al Jazeera described as the first shipping deaths tied to the Houthis since the Iran war began. IMF PortWatch tanker transits fell from about 14 a day to about 9. The sources are press reports only.

Measured effect

Transits, all vessel types, Bab el-Mandeb Strait

Measured on top of an earlier disruption. The baseline was taken while this event was already under way: Attacks on shipping in the Red Sea divert traffic around Africa. The change shown is the change beyond that disruption, not the change from normal.

Baseline (expected): 36.3 transits per day
Observed: 27.4 transits per day
Change: -8.8 (-24.4%)
Standardised score: -1.5
Event window: 2026-07-20 to 2026-09-20 (63 days, provisional)
Baseline window: 2026-05-18 to 2026-07-12 (56 valid days)
Method: wfm-effect-1.1
Computed: 2026-09-22 (22 September 2026), data revision 1:bb8c2268815b

Transits, all vessel types, Bab el-Mandeb Strait, 2026-05-11 (11 May 2026) to 2026-09-13 (13 September 2026): values ranged from 14 transits per day on 2026-08-05 to 47 transits per day on 2026-06-04, with a mean of 32.6 transits per day. The latest value, for 2026-09-13, was 31 transits per day. The shaded band marks the event window, 2026-07-20 to 2026-09-13.

Source: IMF PortWatch (portwatch.imf.org), International Monetary Fund, using UN Global Platform AIS data. Statistics derived by World Freight Monitor. Terms. Retrieved 2026-09-15 (15 September 2026).

Transits, all vessel types, Bab el-Mandeb Strait (transits per day).
Date	transits per day
2026-05-11	30
2026-05-12	45
2026-05-13	38
2026-05-14	38
2026-05-15	24
2026-05-16	38
2026-05-17	34
2026-05-18	45
2026-05-19	45
2026-05-20	37
2026-05-21	35
2026-05-22	38
2026-05-23	42
2026-05-24	46
2026-05-25	37
2026-05-26	26
2026-05-27	40
2026-05-28	42
2026-05-29	30
2026-05-30	32
2026-05-31	33
2026-06-01	41
2026-06-02	38
2026-06-03	31
2026-06-04	47
2026-06-05	28
2026-06-06	41
2026-06-07	37
2026-06-08	31
2026-06-09	38
2026-06-10	32
2026-06-11	41
2026-06-12	41
2026-06-13	38
2026-06-14	33
2026-06-15	35
2026-06-16	25
2026-06-17	42
2026-06-18	41
2026-06-19	41
2026-06-20	39
2026-06-21	37
2026-06-22	30
2026-06-23	30
2026-06-24	37
2026-06-25	46
2026-06-26	36
2026-06-27	32
2026-06-28	37
2026-06-29	36
2026-06-30	38
2026-07-01	32
2026-07-02	39
2026-07-03	31
2026-07-04	31
2026-07-05	34
2026-07-06	29
2026-07-07	27
2026-07-08	32
2026-07-09	29
2026-07-10	27
2026-07-11	44
2026-07-12	41
2026-07-13	46
2026-07-14	46
2026-07-15	40
2026-07-16	33
2026-07-17	46
2026-07-18	40
2026-07-19	33
2026-07-20	35
2026-07-21	26
2026-07-22	31
2026-07-23	34
2026-07-24	30
2026-07-25	22
2026-07-26	20
2026-07-27	32
2026-07-28	33
2026-07-29	34
2026-07-30	38
2026-07-31	28
2026-08-01	20
2026-08-02	30
2026-08-03	17
2026-08-04	27
2026-08-05	14
2026-08-06	31
2026-08-07	30
2026-08-08	25
2026-08-09	34
2026-08-10	29
2026-08-11	25
2026-08-12	25
2026-08-13	20
2026-08-14	31
2026-08-15	40
2026-08-16	36
2026-08-17	29
2026-08-18	32
2026-08-19	33
2026-08-20	29
2026-08-21	21
2026-08-22	33
2026-08-23	29
2026-08-24	36
2026-08-25	25
2026-08-26	26
2026-08-27	21
2026-08-28	27
2026-08-29	20
2026-08-30	29
2026-08-31	24
2026-09-01	19
2026-09-02	38
2026-09-03	24
2026-09-04	32
2026-09-05	18
2026-09-06	23
2026-09-07	34
2026-09-08	22
2026-09-09	35
2026-09-10	27
2026-09-11	22
2026-09-12	20
2026-09-13	31

This is a measured change in public data during the event window, compared with a baseline before it. It shows timing, not cause. We describe an event as causing a change only when an official source says so.

Transits, tankers, Bab el-Mandeb Strait

Baseline (expected): 13.7 transits per day
Observed: 8.3 transits per day
Change: -5.4 (-39.7%)
Standardised score: -1.5
Event window: 2026-07-20 to 2026-09-20 (63 days, provisional)
Baseline window: 2026-05-18 to 2026-07-12 (56 valid days)
Method: wfm-effect-1.1
Computed: 2026-09-22 (22 September 2026), data revision 1:d5d026c34b8d

Transits, tankers, Bab el-Mandeb Strait, 2026-05-11 (11 May 2026) to 2026-09-13 (13 September 2026): values ranged from 2 transits per day on 2026-09-01 to 23 transits per day on 2026-05-24, with a mean of 11.4 transits per day. The latest value, for 2026-09-13, was 9 transits per day. The shaded band marks the event window, 2026-07-20 to 2026-09-13.

Transits, tankers, Bab el-Mandeb Strait (transits per day).
Date	transits per day
2026-05-11	9
2026-05-12	20
2026-05-13	16
2026-05-14	13
2026-05-15	7
2026-05-16	13
2026-05-17	10
2026-05-18	19
2026-05-19	15
2026-05-20	17
2026-05-21	17
2026-05-22	12
2026-05-23	13
2026-05-24	23
2026-05-25	15
2026-05-26	14
2026-05-27	12
2026-05-28	17
2026-05-29	13
2026-05-30	10
2026-05-31	13
2026-06-01	20
2026-06-02	10
2026-06-03	10
2026-06-04	16
2026-06-05	10
2026-06-06	17
2026-06-07	18
2026-06-08	10
2026-06-09	13
2026-06-10	15
2026-06-11	16
2026-06-12	15
2026-06-13	19
2026-06-14	8
2026-06-15	16
2026-06-16	12
2026-06-17	14
2026-06-18	14
2026-06-19	15
2026-06-20	21
2026-06-21	13
2026-06-22	12
2026-06-23	11
2026-06-24	12
2026-06-25	15
2026-06-26	16
2026-06-27	6
2026-06-28	14
2026-06-29	11
2026-06-30	14
2026-07-01	12
2026-07-02	11
2026-07-03	7
2026-07-04	15
2026-07-05	13
2026-07-06	13
2026-07-07	6
2026-07-08	10
2026-07-09	11
2026-07-10	11
2026-07-11	21
2026-07-12	14
2026-07-13	22
2026-07-14	14
2026-07-15	15
2026-07-16	10
2026-07-17	16
2026-07-18	11
2026-07-19	18
2026-07-20	12
2026-07-21	8
2026-07-22	7
2026-07-23	14
2026-07-24	7
2026-07-25	5
2026-07-26	6
2026-07-27	12
2026-07-28	13
2026-07-29	6
2026-07-30	14
2026-07-31	7
2026-08-01	5
2026-08-02	6
2026-08-03	5
2026-08-04	9
2026-08-05	4
2026-08-06	13
2026-08-07	13
2026-08-08	8
2026-08-09	9
2026-08-10	13
2026-08-11	6
2026-08-12	6
2026-08-13	7
2026-08-14	7
2026-08-15	10
2026-08-16	13
2026-08-17	5
2026-08-18	13
2026-08-19	12
2026-08-20	14
2026-08-21	7
2026-08-22	11
2026-08-23	6
2026-08-24	12
2026-08-25	10
2026-08-26	9
2026-08-27	4
2026-08-28	7
2026-08-29	8
2026-08-30	6
2026-08-31	5
2026-09-01	2
2026-09-02	18
2026-09-03	5
2026-09-04	11
2026-09-05	2
2026-09-06	6
2026-09-07	13
2026-09-08	7
2026-09-09	10
2026-09-10	7
2026-09-11	6
2026-09-12	5
2026-09-13	9

Previous computations (4)

2026-09-20, wfm-effect-1.1, revision 1:12c8fa5e5755: observed 34.1 against baseline 32.0 transits per day
2026-09-20, wfm-effect-1.1, revision 1:0a82d319a1ae: observed 10.9 against baseline 11.4 transits per day
2026-09-20, wfm-effect-1.1, revision 1:9ddb07faffb5: observed 8.5 against baseline 13.7 transits per day
2026-09-20, wfm-effect-1.1, revision 1:0fb590e0cfd0: observed 27.8 against baseline 36.3 transits per day

Timeline

2026-07-20The Houthis declare a maritime embargo on Saudi Arabia with immediate effect. [s1]
2026-07-22A maritime security centre warns that Houthi missiles and drones are in place near the strait, and tankers with Saudi cargo turn back. [s2]
2026-08-11A cargo ship named Tihamah is struck by missiles in Bab el-Mandeb, and a second missile hits the rescue effort, according to Yemen government statements reported by Al Jazeera. [s3]

Cause

The Houthis said the embargo answered what they call a Saudi siege of their ports and airports; the announcement followed an attack on Sanaa airport the week before, and the wider US and Israel war with Iran was ongoing. Attributed by: Houthi statement as reported by Al Jazeera. [s1]

Corrections

2026-09-20 (20 September 2026): Removed the two effect targets and set no_effect_reason to insufficient_baseline. Reworded the severity basis to say it is a plain comparison of PortWatch averages, not a method figure.. Reason: The effect engine could not build a baseline because the ongoing Red Sea diversion event covers the same chokepoint for the whole baseline period, so the effect section would have read as pending indefinitely.
2026-09-20 (20 September 2026): Restored the two effect targets and removed no_effect_reason. The severity basis now cites the method figures instead of a plain comparison.. Reason: The effect method was amended the same day (wfm-effect-1.1, ambient events), so a baseline can now be built for an event inside the long-running Red Sea diversion. The figures are measured on top of that disruption and the page says so.
2026-09-20 (20 September 2026): Lowered severity from 4 to 3 and reworded the severity basis.. Reason: The measured fall in total transits (23 percent) is below the 25 percent the rubric needs for level 4, and the standardised scores are weak, so the record is rated on the level 3 criterion of a restriction at a chokepoint.

Sources

[s1] Al Jazeera, Yemen's Houthis declare naval blockade of Saudi Arabia: What to know, published 2026-07-20 (20 July 2026), accessed 2026-09-20. Archived copy. (press)
[s2] CNBC, Houthis ready to attack ships in southern Red Sea, naval group says, published 2026-07-22 (22 July 2026), accessed 2026-09-20. Archived copy. (press)
[s3] Al Jazeera, Six killed in Houthi attack on Bab al-Mandeb ship, Yemen's government says, published 2026-08-12 (12 August 2026), accessed 2026-09-20. Archived copy. (press)
[s4] IMF PortWatch, Daily chokepoint transit calls, Bab el-Mandeb Strait, accessed 2026-09-20. (data)