News
26/09/25
US warns vessels over Houthi Red Sea threat
US warns vessels over Houthi Red Sea threat
Singapore, 25 September (Argus) — The US Maritime Administration has urged
US-flagged commercial vessels to switch off their Automatic Identification
System (AIS) when transiting high-risk waters around the Red Sea and Gulf of
Aden, as Houthi attacks on commercial shipping persist. The guidance, effective
from 23 September, also advises vessels to vary routes and speeds, limit
electronic transmissions and remain as far from Yemen's coastline as safely
possible to make them harder to track and target. The guidance follows a
resumption of attacks by Iran-backed Houthi militants on commercial shipping.
Tankers Daisy , a coastal tanker and Amzan , a very large crude carrier (VLCC)
were struck by Houthi missiles off Yanbu, Saudi Arabia, on 5 and 24 August,
respectively. Yemen's Iran-backed Houthi militant group announced a ban on Saudi
Arabian "maritime navigation" on 20 July, threatening the transit of
Saudi-affiliated vessels through the Bab el-Mandeb strait. The group
subsequently seized the Red Sea port city of Mocha on 11 September, enhancing
the Houthi's ability to disrupt vessel traffic and provide Iran with an
additional means of exerting pressure on international shipping. Vessels with
links to Israel, the US, the UK or Saudi Arabia are considered to be at greater
risk when transiting the southern Red Sea, Bab el-Mandeb and the Gulf of Aden,
according to the advisory. The heightened threat also extends to vessels
belonging to companies or fleets identified as having previously called at Saudi
ports. Potential attacks could involve missiles, aerial or surface drones,
small-arms fire, explosive boats, illegal boardings and vessel seizures, the US
Maritime Administration cautioned. Attacks could also create navigation hazards
for other commercial vessels operating nearby. The US advised its flagged
vessels transiting the Red Sea, Bab el-Mandeb, Gulf of Aden, Arabian Sea and
Somali Basin to switch off AIS unless masters consider doing so a risk to
navigational safety. While ships have previously been attacked with AIS both on
and off, disabling it can make vessels more difficult to track and accurately
target, it said. Ships should also avoid repeating routes, waypoints and speeds
used on previous voyages where possible, while minor changes in course and speed
could also help to complicate targeting. Operators were warned that other
electronic transmissions, including onboard commercial systems and Wi-Fi, could
also reveal vessel information. Ships receiving instructions from the Houthis or
entities claiming to represent Yemeni authorities to divert, activate AIS or
provide voyage information should disregard them and continue their passage
where safe, the advisory said. US-flagged vessels were also advised to
coordinate voyage planning with US naval authorities and immediately report
attacks, suspicious activity or other security incidents. Separately, vessel
traffic through the strait of Hormuz held at 12 crossings on 23 September,
unchanged from 22 September , Windward data show. About 10 vessels were inbound
and two were outbound. Three inbound vessels used the southern US-assisted route
and six took Iran's northern corridor, while both outbound vessels used the
southern route. By Sean Lui, Sureka Elangovan and Jared Bateman Send comments
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