Two Weeks Into the Ceasefire: A Maritime Intelligence Breakdown

At a Glance

• Two weeks into the ceasefire, the Strait of Hormuz remains active only in a restricted and highly unstable sense.
• The brief signal of reopening was overtaken by renewed closure messaging, vessel attacks, and large-scale course reversals.
• U.S. enforcement has expanded from blockade monitoring to active interception, with operations now extending into the Gulf of Oman and beyond the immediate Strait.
• Iranian exports remain active, but with sharper disruption at Kharg Island, lower weekly crude departures, and growing reliance on dark activity, spoofing, and deceptive shipping practices.
• Bandar Abbas and Bandar Imam Khomeini remain heavily congested, with concentrated dark activity and continued evidence of non-transparent maritime flows.
• A large dark tanker cluster near Chabahar points to eastward repositioning under enforcement pressure, with vessels accumulating outside the primary Gulf export zone rather than restoring normal flow.
• IRGC maritime tactics have escalated from deterrence and warning to direct engagement and vessel seizure, materially increasing commercial shipping risk.
• The ceasefire has not stabilized the maritime system, but instead produced a more fragmented environment defined by enforcement expansion, adaptive evasion, suppressed transit, and renewed kinetic risk.

The Second Week of the Ceasefire at Sea

Two weeks after the ceasefire announcement, the maritime system has moved further away from normalization.

The first week of the ceasefire established that Hormuz had not reopened to normal commercial traffic. Movement continued, but under overlapping Iranian control and U.S. enforcement. During the second week, that layered system became more unstable. Transit remained possible, but confidence in predictable passage deteriorated further as enforcement widened, vessel attacks resumed, and operators began reversing course at scale.

The clearest change was that uncertainty gave way to direct disruption. In the first half of the week, U.S. blockade enforcement began producing measurable effects on vessel behavior, with tankers complying with interception orders and Iran-linked traffic continuing under pressure. By the second half of the week, however, the operating picture worsened sharply. Public claims of reopening on April 17 were overtaken within hours by renewed closure messaging, direct attacks on commercial vessels, and large-scale course reversals across both high-risk and standard commercial traffic.

At the same time, Iranian maritime trade did not stop. It adapted. Kharg Island remained active, though at reduced weekly volume. Dark operations persisted around Bandar Abbas and other Iranian ports. A growing cluster of large tankers east of Hormuz near Chabahar suggests that enforcement pressure is forcing repositioning and accumulation outside the Gulf rather than restoring flow through it.

The second week of the ceasefire did not produce stabilization. It produced a more fragmented operating environment in which transit remained suppressed, exports continued under heavier disruption, and the line between military enforcement and commercial shipping risk became even harder to separate.

Hormuz Remains Active, but No Longer Stable

The central signal of the second week is that transit through Hormuz remains possible, but no longer under anything resembling a stable access regime.

On April 17, despite public Iranian statements that the Strait was open to commercial shipping during the ceasefire, the mid-section of the Strait remained empty, with operators holding position rather than committing to transit. 

On April 18, that changed temporarily. Traffic surged as vessels attempted to move before conditions deteriorated. A total of 35 vessels transited the Strait, but the surge was short-lived. Once renewed closure messaging and attacks occurred later the same day, vessels began reversing course at scale. Windward tracked 13 reversals in the immediate aftermath of the closure announcement alone.

By April 19, transit collapsed to just three vessels, marking the lowest level since the blockade began. Volumes partially recovered on April 20 with 15 transits, then dropped again to seven on April 21 and nine on April 22. These day-to-day swings do not indicate normalization. They indicate a system reacting to military announcements, attacks, and enforcement signals in real time.

Two weeks into the ceasefire, Hormuz is still functioning, but under conditions that remain selective, unstable, and highly reactive.

U.S. Enforcement Expanded Beyond the Strait

The second week also marked a clear geographic and operational expansion of U.S. enforcement.

At the beginning of the week, blockade enforcement was already active. U.S. Central Command confirmed that multiple Iran-linked oil tankers had been intercepted and instructed by radio to reverse course, with full compliance and no boarding required. The blockade was being enforced against vessels of all nationalities entering or departing Iranian ports, while allowing unrelated transit.

That enforcement posture then widened. By April 19, the U.S. enforcement activity is now extending beyond the Strait itself. The directive targeted Iranian-flagged ships, OFAC-sanctioned vessels, and the broader shadow fleet infrastructure supporting Iranian trade, while also expanding the definition of contraband to include dual-use goods linked to Iran’s military or war-sustaining economy.

This shift was made operational on April 20 with the first confirmed U.S. interdiction of an Iranian-linked vessel outside the immediate Strait zone. The OFAC-sanctioned Iran-flagged containership TOUSKA was intercepted in the Gulf of Oman while approaching Chabahar from Malaysia. The vessel reduced speed, reversed course, and, after reportedly refusing to comply with U.S. Navy orders, the inspection escalated to kinetic interdiction.

This was a meaningful change. The blockade no longer operates only as a chokepoint control mechanism around Hormuz. It now extends into surrounding waters and is beginning to define a broader interdiction zone aimed at Iranian maritime logistics beyond the Strait itself.

Iranian Exports Remain Active, but Kharg Is Under Pressure

Iranian export flows remained active throughout the second week of the ceasefire, but the structure of those exports showed more visible pressure.

As of April 15, approximately 153.7 million barrels of Iranian oil were on the water, with 84.9% destined for China. Average daily export volumes from Kharg Island between February and April remained elevated at roughly 2.04 million barrels per day. Satellite and AIS analysis also confirmed at least two VLCC departures from Kharg Island around the start of the blockade, both loaded with approximately 2.01 million barrels and bound for Dongjiakou, China.

At the same time, deception remained central to how these flows were sustained. Spoofing behavior was observed around Kharg, including a VLCC reporting a false destination and transmitting a spoofed location west of the island. Dark fleet activity remained elevated, and imagery from April 16 identified seven VLCCs, one Suezmax, and two Aframax vessels in the Kharg region, with three vessels actively loading around 5 million barrels of new cargo.

But by April 23, the pressure on Kharg was more visible. Between April 13 and 19, total crude departures from the island were estimated at approximately 3 million barrels, far below the typical weekly average of around 8 million barrels and the lowest weekly crude export volume since the war began. 

EO imagery from April 18 showed no active loading at the terminals, a rare pause that had not been observed since the start of the conflict. Loading resumed partially by April 20, with a single large tanker, likely a VLCC, loading at the eastern terminal.

This does not suggest that Iranian exports have stopped. It suggests that Kharg is now under more meaningful disruption and that Iran’s primary crude export hub is no longer operating at its earlier wartime pace.

Iranian Trade Is Adapting Through Deception, Congestion, and Eastward Positioning

If Kharg shows disruption, Bandar Abbas and the eastern approaches show adaptation.

Bandar Abbas remained one of the clearest indicators of non-transparent maritime activity. By April 21, Windward detected 296 vessels in the Bandar Abbas and Shahid Rajai area, with only 74 transmitting AIS. The visible fleet was dominated by Iranian-flagged vessels, while a large number of dark detections, including VLCCs, tankers, and large cargo vessels, remained concentrated in the area. 

Ship-to-ship activity was also detected west and north of Larak Island, reinforcing the continued use of offshore transfer operations within Iranian-controlled staging zones.

Bandar Imam Khomeini also remained active. On April 17, 35 AIS-transmitting vessels were present within the port and waiting area, while Windward Multi-Source Intelligence detected 88 vessels in the same area, including eight dark general cargo vessels and two dark tankers that appeared to be heading outbound. This suggests that non-transparent outward movement is not limited to Kharg or Bandar Abbas alone.

The most important adaptive signal, however, came from east of Hormuz. By April 19, seven VLCCs and a ship-to-ship transfer involving two smaller tankers were detected off Chabahar, all operating without AIS. By April 23, the cluster remained in place, with six VLCCs and two Suezmax vessels still stationary and dark, representing roughly 14 million barrels of potential crude transport capacity.

The evidence does not yet point to confirmed new export flows from Chabahar at scale. Instead, the more likely explanation is accumulation and positioning. These appear to be ballast tankers unable or unwilling to re-enter the Gulf under current enforcement conditions, now waiting outside the primary export zone for either re-entry opportunities or alternative routing. The cluster reflects pressure on the system, but also a clear attempt to preserve optionality outside the Strait.

High-Risk Vessels Continue to Probe the System

The second week also showed that blockade enforcement is not producing uniform paralysis.

High-risk vessels continue to probe routes, exploit territorial waters, and test the seams of enforcement. From April 17 to 19, Windward assessed 20 ships as potentially breaking the blockade, including seven sanctioned vessels. These included falsely flagged LPG carriers, sanctioned containerships, and smaller craft operating between Iranian ports and nearby waters.

Some of these vessels used territorial routing to reduce exposure. Two Iran-flagged sanctioned containerships entered Bandar Abbas between April 14 and 18 by hugging Iran’s coastline along the Gulf of Oman. 

A zombie tanker attempted to cross before turning around and returning inbound.

These patterns show that enforcement has raised the cost and risk of movement, but it has not eliminated active testing by shadow fleet and sanctions-linked operators. The system is under pressure, but it is still being actively contested.

Direct Attacks and Seizures Raised the Risk Again

The most serious escalation during the second week came from direct attacks on commercial vessels.

April 18 marked a renewed cluster of incidents near the Strait. SANMAR HERALD, an India-flagged VLCC+ carrying approximately 1.848 million barrels of crude, was fired upon by IRGC gunboats northeast of Oman and later reversed course with cargo undelivered. A container ship was struck by an unknown projectile, while JAG ARNAV, an India-flagged bulk carrier, reported a projectile splash near the Omani coast and immediately aborted transit. MEIN SCHIFF 4, a cruise vessel, also reported a near-miss and a direct VHF threat from IRGC forces before completing transit in convoy.

These incidents directly shaped the reversal wave seen the same day and reinforced that kinetic risk, not only policy or blockade rules, is now driving maritime decisions.

The threat escalated further on April 22. Three outbound container vessels were attacked in a narrow operational window while transiting with AIS switched off. MSC FRANCESCA was fired upon and then seized, later being escorted into Iranian territorial waters. EPAMINONDAS was also fired upon, though the extent of any seizure remained disputed. EUPHORIA was attacked as well, though it successfully cleared the Strait.

This marked a shift from deterrence and stand-off engagement to direct vessel seizure and control. Since February 28, the total number of vessels struck or fired upon has risen to 34. The second week of the ceasefire, therefore, did not lower the threat environment. It pushed it into a more aggressive phase.

Gulf Trade Did Not Normalize. It Became More Reactive

Across the second week, Gulf-wide activity remained heavy, but increasingly reactive.

On April 18, total vessel presence in the Gulf rose to 919, then fell to 870 on April 20, 760 on April 21, and back to 868 on April 22. These swings reflect a system releasing stalled traffic in some windows, then rebuilding congestion in others. Dark activity declined at times, but remained elevated throughout.

This is not a market returning to flow. It is a market continuously adjusting to military announcements, attacks, enforcement actions, and route risk. Even when transit volumes partially recover, the surrounding system remains unstable.

Outlook

Two weeks into the ceasefire, the direction of travel is clear.

Hormuz remains active, but not stable. The brief signal of reopening was overtaken by renewed closure messaging, vessel attacks, and large-scale reversals. Transit still occurs, but under conditions that remain selective, highly reactive, and vulnerable to abrupt deterioration.

At the same time, U.S. enforcement has widened from blockade monitoring to active interdiction, with operations now extending into the Gulf of Oman and toward a broader campaign against Iran-linked maritime networks. This is increasing pressure on Iranian shipping, but it is also pushing adaptation rather than producing a halt.

Iranian trade remains active through a mix of dark operations, spoofing, fraudulent flagging, and congested port behavior. Kharg exports have slowed sharply, Bandar Abbas remains dense and opaque, and the Chabahar cluster suggests that tanker positioning is shifting eastward under enforcement pressure rather than unwinding.

The second week of the ceasefire has therefore produced a more fragmented system than the first. The core pattern is no longer just overlapping control. It is overlapping control plus renewed direct disruption.

For now, normalization is further away than it appeared a week ago. The maritime system is still functioning, but through suppressed transit, adaptive positioning, expanding interdiction, and a higher tolerance for direct engagement against commercial shipping.