Iran War Shipping Update - May 28, 2026

Since the outbreak of the Iran War on February 28, Iran’s “Ghost Fleet” has continued operating across key maritime routes, including loading cargoes, transiting the Strait of Hormuz, and sailing east toward China. While UANI tracking indicates that illicit shipping activity remains ongoing, the U.S. blockade initiated on April 13 is now constraining Iran’s export capacity. The blockade targets vessels entering and exiting Iranian ports, as well as ships transporting sanctioned oil or contraband cargo, but does not apply to all Iran-linked maritime traffic. U.S. enforcement efforts have focused primarily on VLCC tankers, while smaller and support vessels continue to operate.

To read UANI’s statement on FAQs and keys facts about the U.S. blockade, click here. 

To read UANI's statement on why U.S. pressure on Iran's oil exports is working, click here.

On May 28, U.S. CENTCOM posted that U.S. forces have redirected 111 commercial ships and disabled 4 to prevent ships from entering or leaving Iranian ports since the commencement of the blockade.  

U.S. CENTCOM update on the U.S. blockade on May 27 (Credit: U.S. CENTCOM/X)

Status of the Strait of Hormuz

The Strait of Hormuz remains a critical flashpoint in the Iran War. Since the start of the conflict, 44 confirmed maritime incidents involving commercial vessels and offshore infrastructure have been reported across the Persian Gulf, Strait of Hormuz, and Gulf of Oman. 

The enduring risk has created severe congestion and instability across the Persian Gulf’s shipping lanes. Prior to the outbreak of hostilities, about 138 vessels transited the Strait of Hormuz daily. Since March 1, 2026, marine traffic data shows growing clusters of loitering vessels on both sides of the Strait of Hormuz, with many refraining from transiting due to safety concerns.

Speculation over a possible Memorandum of Understanding with Iran is growing, which would result in the Strait of Hormuz being opened in exchange for the ceasing of the U.S. naval blockade and other steps. For now, however, the diplomatic situation remains uncertain, and no agreement has been announced.

IRGC efforts to restrict Freedom of Navigation

The IRGC’s newly announced so-called “Persian Gulf Strait Authority” (PGSA) published a proposed scheme for controlling and restricting freedom of navigation through the international strait.  Such measures are in direct contradiction to UNCLOS Article 44, “Duties of States bordering straits,” which states:

“States bordering straits shall not hamper transit passage and shall give appropriate publicity to any danger to navigation or overflight within or over the strait of which they have knowledge. There shall be no suspension of transit passage.”

Any attempt to impose unilateral restrictions on transit passage through an international strait undermines the internationally recognized navigational rights guaranteed under UNCLOS.

IRGC PGSA tweet on May 21 (Credit: X)

The U.S. Department of the Treasury’s Office of Foreign Assets Control (OFAC) took action and designated Iran’s so-called Persian Gulf Strait Authority (PGSA) on May 27.

Iranian Oil-Laden Tankers Inside the U.S. Blockade

UANI has identified at least 67 tankers laden with Iranian oil — primarily crude, but also other petroleum products and LPG — currently operating inside the U.S. blockade line which can be drawn from the Iranian-Pakistan border to the most eastern point of Oman. 

Map of Iranian oil laden tankers inside the U.S. blockade on May 28

Iran-linked Vessels at Kharg Island, Iran

Satellite imagery from May 26 indicates an accumulation of tankers at the Kharg Island anchorage, idle offshore. 21 tankers were spotted in the anchorage area, at least 13 of which are laden with Iranian hydrocarbons. The buildup of tankers anchored here suggests increasing disruption to Iran’s crude export flows due to the ongoing US blockade, particularly shipments destined for China’s independent “teapot” refineries. 

Iran linked tankers anchored near Kharg Island on May 28 (Credit: ESA Copernicus)

Number of Iranian Loadings

Since the outbreak of the conflict, UANI has tracked at least 80 Iranian oil loadings, 45 of which originated from Kharg Island, Iran. These shipments represent approximately 85 million barrels of Iranian oil, generating an estimated revenue of over $6 billion for the IRGC, which continues to fund Iran’s active missile and drone programs central to the conflict. This figure is notably higher than usual given the sharp increase in oil prices, including Iranian crude.

Iran-linked Vessels at Chabahar Port, Iran

Iran-linked tankers are loitering and anchoring outside of the Persian Gulf at Chabahar Port, Iran. On May 26, 14 tankers, including 11 Iran-flagged tankers, as well as three dark fleet vessels, all laden with Iranian oil, were observed in satellite imagery near Chabahar Port. Numerous Iran-flagged and Iranian oil-laden tankers that have attempted to cross the blockade departed from Chabahar Port, with at least eight of these returning to port in response to a variety of U.S. enforcement actions. 
 

Iran linked tankers anchored near Chabahar on May 26 (Credit: ESA Copernicus)

Iran-linked Vessels near Sri Lanka

Iran-linked tankers have been anchoring about 20 km offshore from Galle, Sri Lanka, likely for logistical support from local service providers but also in response to pressure from the U.S. blockade. On May 24, three Iran-flagged tankers, all unladen, plus two UANI Ghost Armada tankers, one of which carrying Iranian crude, were anchored near Galle. 

Iran-flagged Tankers Globally

UANI has also monitored Iran-flagged tankers operating beyond the Persian Gulf. Since the conflict began, at least 32 Iran-flagged tankers have reached Southeast Asian waters bound for the Eastern Outer Port Limits (EOPL) anchorage off Johor, Malaysia. 

Meanwhile, at least 35 Iran-flagged tankers, reporting empty, have begun attempts to return to Iran and from the Malaysian EOPL anchorage and Southeast Asian sea lanes, since the start of the conflict.

Iran-Oil Laden Tankers off the Malaysian Coast

From February 28, the start of the conflict, to today, UANI has recorded 69 STS transfers of Iranian crude oil and 5 STS transfers of LPG in the EOPL anchorage, a ghost fleet hotspot approximately 70 km off Malaysia’s coast. All of these transshipments have been spotted in satellite imagery.

On May 28, 40 tankers listed on UANI's Ghost Armada were anchored or loitering near the EOPL area with their AIS signals active, demonstrating that ghost fleet tankers continue to operate with impunity across Southeast Asia's sea lanes. 

Iran-Flagged Cargo Ships Globally

Despite ongoing pressure of US OFAC sanctions, approximately 40 Iranian flagged vessels continue to operate openly across sea lanes, ports, and anchorages throughout the Indo-Pacific region. Enhanced pressure from the enforcement of the US blockade on Iran and disrupted access to Iranian ports appears to be affecting vessel schedules and operations on a large scale which has contributed to increased instances of ships pausing and waiting in clusters at anchorages across the region. There is a risk of Iranian flagged cargo ships carrying contraband cargo in violation of US blockade. 

Iran-flagged vessels across the Indo-Pacific on May 28 (Credit: Marine Traffic)

In May 28, there were no significant changes to the multiple Iranian flagged tankers and cargo vessels that continued to anchor offshore of Karachi, Pakistan.  The cargo ships ARIES (IMO 9369722), MAHNAM (IMO 9213387), DELRUBA (IMO 9305207), WARTA (IMO 9465849),and PARNIA (IMO 9167265) were broadcasting on AIS while anchored about 60km offshore in the Pakistani Exclusive Economic Zone (EEZ). The tankers STREAM (IMO 9569633), HERBY (IMO 9362059), SOBAR (IMO 9221970) and SARAK (IMO 9226968) are also anchored nearby. The container ship TOUSKA (IMO 9328900) remained anchored just 16 km outside Karachi port, inside Pakistani territorial waters. All of these Iran-flagged vessels are OFAC sanctioned. At least 10[CB1]  other non-Iranian flagged Ghost Armada tankers are also anchored in the Pakistan EEZ.

Iran-flagged cargo vessels near Karachi, Pakistan on May 28 (Credit: Marine Traffic and ESA Copernicus)

The OFAC sanctioned, Iran-flagged container ship ARTENOS (IMO 9283021) continued to loiter at anchor in the Gulf of Kutch, outside Kandla, India. The vessel has been anchored for four weeks since it conducted unknown cargo operations in Kandla Terminal between April 18 and 19. 

Credit: Marine Traffic and ESA Copernicus)

On May 28, four OFAC sanctioned, Iran-flagged cargo ships were sailing in the vicinity of India: in the Arabian Sea and also the Bay of Bengal.

The container ship ENZO 2 (IMO 9236652) continued sailing across the Arabian Sea. The destination is listed was updated to Mumbai, India on its AIS signal, with an ETA of May 29.  This is a change from the previously listed destination of Singapore. ENZO 2 departed Misurata, Libya on May 15, and transited the Suez Canal on May 19.

The Iran flagged container ship ARTABAZ (IMO 9283007), continued sailing southerly direction, and showed a new destination on AIS of Male, Maldives with an ETA of May 30. This is a change from the previously displayed destination of Mombasa, Kenya.   

The Iran flagged container ship NYRA 2 (IMO 9241487) continued sailing west with a destination listed on AIS as Port Klang, Malaysia with an ETA of June 4.  The ship departed Misurata, Libya on May 17, and transited the Suez Canal on May 20. 

The Iran-flagged container ship AZARGOUN (IMO 9283019) continued to sail south in the Bay of Bengal, towards Sri Lanka. It completed cargo ops and departed Chennai, India, on May 27 after arriving in the terminal earlier on the same day. Its destination is listed on AIS as Mumbai, India, with an estimated arrival time of June 3. AZARGOUN had previously departed the Malaysian EOPL on May 19, briefly stopping at the Port Klang anchorage, before transiting to Chennai.

Iran-fgged container ships in Arabian Sea on May 28 (Credit: Marine Traffic)
 

The Iran-flagged, OFAC sanctioned container ship VELON 1 (IMO 9122473) continued sailing eastward in the Bay of Bengal, toward the Malacca Strait. On May 28, it was approaching the Six Degree Channel between the northern tip of Sumatra, Indonesia, and the southern point in the Anaman & Nicobar Islands of India.  The vessel departed Novorossiysk, Russia on April 23, after unknown cargo operations, and transited the Suez Canel on May 9. VELON 1 is currently reporting on AIS that it is laden. On May 21, it changed its reported destination from Port Klang, Malaysia to Singapore with an estimated arrival time of June 2.

Iran-flagged container ship approaching the Malacca Strait on May 28 (Credit: Marine Traffic)

On May 28, there was no change to the OFAC-sanctioned Iran-flagged bulk cargo ship KIAZAND (IMO 9465758), which continued to anchor just offshore Phuket Port, after completing unknown cargo operations. It arrived at the terminal on May 20, after anchoring since May 18, and still reporting that it is in ballast condition. 

Iran-flagged cargo ship in Phuket on May 28 (Credit: Marine Traffic and ESA Copernicus)

On May 28, the OFAC sanctioned, Iran-flagged general cargo ship AREZOO (IMO 9165786) and container ship RADIN (IMO 9820257) continued to remain anchored outside Port Klang, Malaysia, in the Malacca Strait. AREZOO has been anchored at Port Klang since April 16, conducting unknown cargo operations in the container terminal on April 17-18. RADIN has been anchored here since May 5 but has not yet conducted cargo operations in port. 

Iran-flagged cargo ships near Port Klang, Malaysia on May 28

(Credit: Marine Traffic and ESA Copernicus)

On May 28, six Iran-flagged cargo ships remained anchored in or near the Malaysian EOPL anchorage area, openly broadcasting on AIS: the bulk cargo ships ARVIN (IMO 9193202), MIAMI PRIDE (IMO 9274941), BASKAR (IMO 9405942), ANDIA (IMO 9193197), BAHJAT (IMO 9405954) and the container ship OURA (IMO 9387815). These OFAC sanctioned vessels are likely waiting in the EOPL due to the U.S. blockade. 

Iran-flagged cargo ships at Malaysian EOPL on May 28 (Credit: Marine Traffic and ESA Copernicus)
 

On May 28, three Iran-flagged container ships SHABDIS (IMO 9349588) and SHABGOUN (IMO 9346524) and BEHNAVAZ (IMO 9346548) remain anchored in the vicinity of Zhuhai, China. BEHNAVAZ completed cargo operations in Zhuhai port on May 26 and returned to the anchorage today. Zhuhai Port at Gaolan Island has been identified in media reports as a source of precursor chemicals for rocket fuel.

Meanwhile, the Iranian flagged tanker TOUR 2 (IMO 9364112), also known as KARIZ, was spotted maneuvering again in satellite imagery while broadcasting its AIS signal on May 27. It is still reporting on AIS that it is laden with cargo and has no new destination identified. KARIZ and another vessel claiming to be RYO (IMO 9299355), a previously decommissioned tanker, appeared to merge tracks, suggesting a possible swapping of AIS identities to obscure illicit Ship-to-Ship (STS) operations. 

Iran-flagged container ships at Zhuhai, and tankers south of Hong Kong China, on May 28  
(Credit: Marine Traffic and ESA Copernicus)

The Iran-flagged bulk cargo ship ROSHAK (IMO 9405966) continued to sail south through the Bashi Channel into the South China Sea. It departed its anchorage in Bohai Bay after completing unknown cargo operations at Huanghua bulk cargo terminal on May 17. The bulk cargo ship stopped briefly in the CJK anchorage near Shanghai from May 23-25 and is now reporting laden status, with the destination of Songkhla, Thailand on June 3.

Iran-flagged cargo ship sailing east of Taiwan on May 28 (Credit: Marine Traffic)