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Iran Conflict 2026
11MAY

GPS blacked out across Gulf chokepoints

2 min read
14:01UTC

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.

ConflictDeveloping
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
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Different Perspectives
International human rights monitors (NetBlocks, IHR, Hengaw)
International human rights monitors (NetBlocks, IHR, Hengaw)
NetBlocks recorded 1,704 cumulative hours of near-total internet blackout for roughly 90 million Iranians on Day 74, while IHR documented ongoing executions under emergency provisions. These organisations are the only active monitoring windows into a civilian population cut off from the global internet for 71 consecutive days.
UK / France coalition
UK / France coalition
The Royal Navy confirmed HMS Dragon's Hormuz deployment on its own website on 11 May, converting a press-reported presence into declared force posture; UK and French defence ministers hosted a coalition meeting the same day. Britain and France are now the only named contributors to a Hormuz escort mission all five allies Trump originally asked had declined.
Saudi Aramco / Gulf producers
Saudi Aramco / Gulf producers
Saudi Aramco CEO Amin Nasser warned on 11 May that a Hormuz closure could remove 100 million barrels of weekly supply from global markets (roughly 15 million barrels per day for a week), a figure that dwarfs any OPEC+ swing capacity. The warning functions as both a price-floor signal and a public pressure on Washington to protect transit.
Beijing / Chinese Government
Beijing / Chinese Government
China has not publicly acknowledged the four Hong Kong-registered entities designated on 11 May or extended MOFCOM's Blocking Rules cover to HK-domiciled firms. Xi Jinping hosts Trump on 14–15 May having already de-risked state-bank balance sheets via NFRA's quiet loan halt, entering the summit partially compliant before any negotiation.
Tehran / Iranian Government
Tehran / Iranian Government
Foreign Minister Araghchi described Iran's 10-point counter-proposal as 'reasonable and responsible' via spokesman Baqaei on 11 May, and widened the mediator pool by meeting Turkish, Egyptian, and Dutch counterparts in a single day. Tehran is buying procedural runway while Trump's verbal rejection went unmatched by any written US counter.
Trump White House
Trump White House
Trump called the ceasefire 'on massive life support' and dismissed Iran's 10-point counter-proposal as 'a piece of garbage' on 11 May, while departing for Beijing two days later with no signed Iran instrument to show Congress. The verbal maximum and the paper void coexist: the administration is running a legal pressure campaign through Treasury while the president free-lances the rhetoric.