Iran has effectively halted most tanker traffic through the Strait of Hormuz since late February 2026, keeping the waterway closed to vessels linked to “Iran’s enemies.” Tehran’s UN envoy confirmed that the strait is open only to ships not associated with the U.S., Israel, and their allies. Satellite data show oil tanker traffic through Hormuz has plunged, effectively paralysing the chokepoint and sending global oil prices sharply higher. In practice, Iran has allowed only a trickle of maritime traffic, demanding tolls or safe-passage fees for passage and even charting a new safe route north of the traditional channel. Iran’s Islamic Revolutionary Guards Corps (IRGC) has warned that any military vessels approaching the strait will face a severe response and insisted on using the new route due to the likelihood of various anti-ship mines in the main traffic zone. In sum, before the US intervention, Iran had effectively mined and closed most of Hormuz to foreign shipping, enforcing a de facto blockade against its declared enemies.
On 12–13 April 2026, President Donald Trump on his Truth Social described Iranian tolls as an illegal act of extortion and instructed US forces to immediately blockade the Strait of Hormuz. Though the official US Central Command (CENTCOM) statement clarified the blockade covers only Iran’s coastline, not innocent passage through the international waterways. CENTCOM specified that the blockade will be enforced impartially against vessels of all nations to or from Iranian ports and coastal areas, but it will not impede freedom of navigation for vessels transiting the Strait of Hormuz to and from non-Iranian ports. Thus, the official US policy was a maritime embargo around Iran, not a physical blockade of the strait itself.
On 13 April CENTCOM broadcast a radio message to mariners warning that any vessel entering or departing the blockaded area without authorization is subject to interception, diversion, and capture. A naval Notice to Mariners reiterated the blockade’s geographic scope, from Iran’s Gulf coast east into the Gulf of Oman and Arabian Sea, and confirmed humanitarian shipments would be exempt, subject to inspection.
Previously on 11 April, CENTCOM had announced that two US Navy guided-missile destroyers, USS Frank E. Peterson and USS Michael Murphy, had transited the strait to begin setting conditions for clearing mines that Iran’s IRGC had laid. CENTCOM Commander Adm. Brad Cooper said the mission would establish a new passage and share that safe pathway with the maritime industry to restore commerce. Additional undersea drones and forces were to join the clearance operation in the coming days. President Trump confirmed this on 16–17 April, tweeting that Iran, with the help of the U.S.A., is removing all sea mines from the strait.
Iran had in fact deployed a mix of contact and influence mines, such as its domestically produced Maham-3 and Maham-7 bottom mines, in strategic channels. Iran’s IRGC released its own navigation map calling north-of-Larak routes safe, implicitly acknowledging mine hazards in the conventional channel. US clearing would rely on unmanned mine-hunting vehicles, sonar-equipped helicopters, and expendable mine-neutralization systems. Analysts note that even a single mine can force insurers and shippers to treat the entire area as off-limits, so the US emphasis on demining was partly to negate Iran’s leverage over global trade.
By 14 April, CENTCOM reported that no vessel had breached the blockade and that multiple merchant ships had been forced to divert. Reuters noted that 6 merchant vessels complied with US orders to turn around within the first 24 hours of the blockade. By 16 April, CENTCOM’s public statements had tallied a total of 10 ships turned back during the first 48 hours. These included an Iranian-flagged cargo vessel exiting Bandar Abbas that was intercepted by USS Spruance and redirected back toward Iran. By April 17, US officials said 19 ships had complied with blockade directions and zero had successfully evaded.
The blockade force, estimated at over 10,000 troops; 16 US warships, 11 destroyers among them; plus allied vessels, was enforcing compliance well away from the strait itself. In practice, ships approaching the blockade, even outside Iranian territorial waters, have been warned on radio that they risk interception or boarding if they proceed to Iranian destinations. Most owners have opted to halt or reverse course: tracking firms reported at least 14 ships turned back in the first three days. Some vessels bound for Iran even went dark or loitered offshore rather than face interception.
Notable cases include the Rich Starry, a 188m Chinese-owned tanker, which departed Sharjah on April 13 for China but was ordered by US forces to reverse course minutes before reaching Hormuz. Similarly, the Greek-owned tanker Ostria was turned around in the Strait of Hormuz on April 13. A heavily laden Pakistani tanker, Shalamar, first attempted to sail into the Gulf on Sunday but was aborted under US pressure; she eventually left later on 17 April after loading in the UAE, becoming the first crude-laden ship to exit Hormuz since the blockade. All ships that had been in Iranian ports at the blockade’s start were given a grace period to depart before restrictions kicked in, and about a dozen vessels reportedly left Iran safely under this allowance. By contrast, any Iranian-flagged ship attempting exit has been ordered to reroute: CENTCOM emphasized the blockade is impartial and applies to Iranian and foreign vessels alike.
Despite the blockade on Iran-bound traffic, routine international passage through the Strait of Hormuz continued at a reduced rate. Reuters data showed that at least eight vessels, mostly not heading to Iran, passed through on 13–14 April, including three tankers tied to Iran’s oil trade and other commercial ships. For example, the Panama-flagged tanker Peace Gulf, carrying Iranian naphtha, transited toward the UAE, and the handy tanker Murlikishan (formerly MKA) passed southbound for Iraq on April 13. On April 14, the sanctioned Malaysian tanker Murlikishan sailed through en route to Basra, as did the Chinese-sanctioned vessel Rich Starry, which became the first such tanker to exit the Gulf since the blockade, though she later returned and anchored off Iran. Two very large crude carriers, Alicia and Agios Fanourios I, were also seen entering the Gulf via Hormuz on 15 April to load Iraqi crude.
Some Iranian oil products did flow out just before the blockade began. According to Reuters, on 13 April the 50,000‑ton tanker Aurora and the tanker New Future departed the Gulf via Hormuz before the US embargo took effect. However, no Iranian oil tankers have reportedly successfully exported crude through the strait since 28 Feb, as Iran has held its own stockpiles onshore.
New Asia-bound traffic also found its way around the Gulf. On 17 April, the Shalamar (Pakistan-flagged) transited out of Hormuz loaded with 450,000 barrels of UAE crude, according to tracking data. Likewise on 17 April the Hong Kong-flagged LPG tanker AVA 6 passed through Hormuz southbound (originating in the UAE). Before the blockade, other ships such as Ocean Energy (a general cargo ship) docked at Bandar Abbas and transited normally. In all cases, these vessels were heading to non-Iranian destinations and so fell outside the embargo. Oil-price-sensitive flows resumed: shortly after Iran’s opening announcement, markets reacted to the news of resumed tanker traffic. War-risk insurance costs remained sky-high, but carriers cautiously began moving under flags or charterers that did not have Iranian exposure.
On 17 April, as the Lebanon ceasefire took hold, Iran’s government declared that the Strait of Hormuz was completely open for all commercial ships under a coordinated route. Foreign Minister Abbas Araghchi said that for the remainder of the ceasefire any commercial vessel could use the previously announced northern channel. President Trump almost immediately echoed Iran’s announcement on Truth Social, posting that the strait was COMPLETELY OPEN and ready for passage. He also insisted that his naval blockade on Iran would remain in effect until a 100%-complete deal with Tehran, but confirmed that the waterway itself was no longer closed to neutral shipping. However, Trump’s insistence on maintaining the naval blockade along Iran’s coastline prompted a swift response from Tehran, with the Islamic Revolutionary Guard Corps (IRGC) announcing on 18 April 2026 that the Strait of Hormuz would be closed once again.
Crucially, Trump’s post on April 17 included a celebratory “Thank you!” after noting that Iran, with the help of the U.S.A., is removing all sea mines. This line signaled U.S.-Iran coordination on de-mining under the ceasefire. The U.S. had also publicly offered to keep the strait clear if Iran would cease using it as a weapon. In summary, by 17 April commercial shipping was officially flowing again: Iran’s reopening declaration and Trump’s approval marked the end of the stand-off that had held up some 230 tankers in the Gulf. Throughout the crisis, no ships were sunk or boarded under the U.S. blockade, but dozens were diverted, by CENTCOM’s count at least 19, and many routes remained disrupted.
The decision to reopen the Strait of Hormuz appears to have generated significant internal dissent within Iran’s power structure. Multiple regional analyses and media monitoring of statements suggest that hardline Iranian factions view the strait closure as a critical strategic lever against the United States and its allies. The earlier imposition of transit restrictions, combined with the deployment of naval mines and selective passage policies, had effectively enhanced Iran’s deterrence posture. As a result, the reopening, particularly under conditions perceived as involving concession, has been interpreted by some within the IRGC and conservative political circles as a rollback of hard-earned leverage.
Internal tensions within Iran are increasingly focused on Abbas Araghchi, who has become a central target of both public and elite criticism. Iranian state media and political discussions portray that he is being openly challenged for his role in reopening the strait and engaging in indirect concession during the ceasefire. This reaction is similar to what happened earlier to Javad Zarif and Hassan Rouhani, who faced strong backlash and even reported death threats in early April for supporting negotiations. This pattern shows that many within Iran’s establishment still strongly oppose diplomacy if it is seen as weakening the country’s strategic position. Experts also point out that when such criticism appears in state-linked media, it often reflects deeper disagreements among powerful groups, not just public opinion.
At the same time, Iran’s leadership structure in this situation appears unclear and somewhat divided. Mojtaba Khamenei does not seem to be playing a clear or leading role. Instead, key decisions appear to be made by figures like Mohammad Bagher Ghalibaf, Abbas Araghchi, and Ahmad Vahidi. This points to a divide within the system: on one side are the IRGC and hardliners who favor a tough, resistant approach, and on the other are more pragmatic officials who are willing to reduce tensions when necessary. In a broadcast by the IRIB (Islamic Republic of Iran Broadcasting), the speaker sharply criticizes Araghchi while also lamenting that the consistent efforts of regime supporters, who turned out daily for rallies during Ramadan, may have been undermined by recent decisions.
In broader strategic terms, however, the core issues driving the confrontation remain unresolved. Iran’s nuclear program, ballistic missile development, and support for regional proxy groups continue to be treated as non-negotiable by the United States and remain central to ongoing negotiations. Within this context, the reopening of the Strait of Hormuz, even if temporary, represents a significant tactical concession by Iran to both the United States and Gulf Cooperation Council (GCC) states. It signals a limited, situational compromise aimed at stabilizing maritime trade and reducing immediate economic pressure, rather than any fundamental shift in Iran’s long-term strategic posture.
Maritime traffic observations by BDJ on 18 April 2026 indicate that The Pushpak (IMO 9383340), an asphalt/bitumen tanker built in 2007 and sailing under the Cook Islands flag, transited the strait before its reopening was publicly announced on 17 April 2026. Following the announcement, a noticeable increase in vessel movement toward the strait was observed. However, several ships altered course or halted due to prevailing uncertainty. For instance, Titan Harmony (IMO 9279202), an oil/chemical tanker sailing under the Barbados flag, and Trend (IMO 9477177), an oil products tanker under the Togo flag, both diverted from the strait. In contrast, other vessels continued their approach, including Desh Suraksha (IMO 9467768), a crude oil tanker under the Indian flag; and Nissos Keros (IMO 9856074), a crude oil tanker sailing under the Marshall Islands flag. The flow of vessels heading toward the strait is largely dominated by ships bound for India and China.
Following the reannouncement of the strait’s closure, the vessels mentioned above, along with several others already in or approaching the area, were observed altering course and turning away from the strait. This widespread reversal in movement effectively confirms that the strait has been reclosed in practice, as ships responded immediately to the renewed restrictions and heightened risk.
After a prolonged period of disruption that left numerous vessels stranded, the sudden reopening of the Strait of Hormuz triggered a surge of ships attempting to transit the passage. However, with sections of the strait reportedly mined, the navigable corridor was effectively narrowed, significantly increasing operational risks. The resulting congestion heightened the likelihood of vessels striking mines or colliding with one another without strict coordination. While the reopening initially signaled a return to normalcy, the situation remained highly fragile and dependent on political developments.
Global markets and maritime operations have been deeply affected throughout this period. Even without direct attacks, the perception of risk led insurers to classify the area as unsafe, disrupting shipping patterns and driving volatility in oil markets. The announcement of the strait’s reopening briefly boosted confidence, including a positive reaction in U.S. markets, illustrating how sensitive global systems are to developments in this chokepoint. However, uncertainty persisted, as reflected in vessels reversing course and inconsistent movement patterns. Despite official declarations, a clear gap remained between political messaging and operational realities on the ground.
This fragility was quickly exposed when the Islamic Revolutionary Guard Corps reannounced the closure of the strait on 18 April 2026, following U.S. insistence on maintaining a blockade of Iranian ports until a comprehensive agreement is reached. What initially appeared to be a stabilizing step, the reopening, rapidly unraveled due to continued strategic pressure. The sequence of events highlights how a single policy decision can reverse momentum and escalate tensions in an already volatile environment.
The situation now points toward a heightened risk of direct confrontation between Iran and the United States. Earlier indications of limited coordination, particularly around mine-clearing operations, have given way to renewed hostility. With an increased U.S. military presence in and around the strait, the operational environment is shifting from cautious de-escalation to potential conflict. The rapid cycle of opening, political signaling, and reclosure underscores the absence of trust between the parties and the instability of any temporary arrangements.
The implications extend beyond the maritime domain. Although a ceasefire in Lebanon had been implemented, renewed tensions in the strait risk undermining it. The reclosure may either directly destabilize the ceasefire or be used as justification by involved actors to violate it. In essence, the sequence, reopening of the strait, continued U.S. pressure, and Iran’s swift reclosure suggest a trajectory toward broader regional escalation, with the Strait of Hormuz once again at the center of geopolitical confrontation. Following the sudden reclosure, there is concern that enforcement may involve direct targeting of vessels, and that some ships may already have sustained damage as a means of deterrence and to ensure compliance with the renewed restrictions.
For further background understanding, Bangladesh Defence Journal has more work here, here, here, and here.
Verification Note: The information in this report has been compiled from multiple credible sources and cross-checked for consistency. Data and reports have been used to corroborate events where possible. While every effort has been made to ensure accuracy, access limitations may prevent independent verification of all details. MarineTraffic.com was used to access vessel movement data.
Ahsan Tajwar is a Security and Strategic Reporting Fellow at the Bangladesh Defence Journal. His work focuses on law enforcement, terrorism, transnational crime, organized trafficking networks, and cross-border security dynamics. He is currently pursuing a B.S.S. in Criminology. His analysis relies heavily on an academic approach, with particular emphasis on their socio-cultural dimensions.