Skip to content
You can now search across every topic, entity and event.What's new
European Oil Markets
18JUN

GPS blacked out across Gulf chokepoints

2 min read
12:45UTC

US and British maritime authorities confirm an electronic warfare corridor stretching 2,500 kilometres across two of the world's three critical sea lanes. There is no safe detour.

EconomicDeveloping
Key takeaway

An electronic warfare corridor now links two chokepoints, leaving no safe maritime alternative.

MARAD Advisory 2026-004 and UKMTO data confirm severe GNSS/GPS interference extending from the strait of Hormuz across The Gulf of Oman and into the Red Sea near Bab al-Mandeb 1. This is not a side effect of military operations but a deliberate electronic denial zone spanning two of the world's three critical maritime chokepoints.

No modern peacetime precedent exists for electronic warfare denial at this scale. During the Tanker War (1987 to 1988), mines and missile boats threatened individual vessels. The current denial threatens the navigational infrastructure itself, degrading the ability of any vessel to determine its own position across a 2,500-kilometre corridor. The Houthis threatened Bab al-Mandeb closure the day after Pakistan confirmed talks had stalled.

Vessels diverting from Hormuz toward the Red Sea now navigate degraded positioning systems approaching a second contested chokepoint. Roughly 4.5 million barrels per day and 12% of global trade pass through Bab al-Mandeb. Combined with near-total Hormuz closure, the world's two most important oil chokepoints are under simultaneous pressure for the first time since the 1973 oil crisis 2. The Cape of Good Hope route adds 10 to 14 days and $500,000 to $1 million per voyage in fuel costs.

Deep Analysis

In plain English

Ships navigate using GPS-style satellite signals. Someone is deliberately jamming those signals across a 2,500-kilometre corridor stretching from the Strait of Hormuz in the Gulf to the Bab al-Mandeb in the Red Sea. This matters because ships diverted away from Hormuz (which Iran controls) have been heading toward the Red Sea instead. The GNSS jamming makes that alternative route significantly more dangerous, because ships cannot accurately determine their own position. The practical effect: there is now no safe, insurable sea route between the Gulf and global markets. Ships must go around Africa instead, adding 10 to 14 days and significant fuel costs to every voyage.

First Reported In

Update #51 · Iran hits aluminium plants; Hormuz emptying

International Maritime Organisation / UKMTO· 29 Mar 2026
Read original
Different Perspectives
Gulf oil producer
Gulf oil producer
Secured OPEC's confirmed 188,000 b/d September increment with the next meeting set for 6 September, but the Secretariat's own 2 August release says nothing about the fourth quarter. Output guidance beyond September remains undisclosed even as delegate sourcing keeps filling that gap.
Money manager positioned in WTI
Money manager positioned in WTI
Added 21,402 lots to a 108,307 net long in NYMEX WTI in the week to 28 July, against just 1,485 added to Brent's 15,740, a roughly fourteen-to-one split. Conviction sits in the American benchmark even as the European diesel story sets the record.
Indian refiner buying Urals
Indian refiner buying Urals
Bought Russian crude at a discount that narrowed to $1-2 a barrel in the week to 29 July from over $10, as Hormuz risk pushed it toward Urals. If that risk eases with the strike now called off, the discount it is currently enjoying could re-widen just as fast.
Russian diesel exporter
Russian diesel exporter
Novak tied any lifting of the diesel export ban, due to lapse 31 July, to an unspecified market recovery with no date, and pushed the gasoline ban to end-2026. An open-ended constraint suits an exporter benefiting from the record European crack it feeds.
War-risk underwriter
War-risk underwriter
Withdrew war-risk cover for Saudi-linked hulls on 24 July and has not reinstated it, holding Bab el-Mandeb tanker transits near 7.5 a day. A cancelled strike does not by itself trigger the committee review needed to re-accept the class.
Northwest European refiner
Northwest European refiner
Sources only 17% of diesel imports from Saudi Red Sea ports against the Mediterranean's 24%, so the ARA crack at $85.86 trails the Med print by $5.81. Lower Red Sea exposure is cushioning it against the rerouting cost, not eliminating it.