Iran War Shipping Update - May 20, 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 or contraband oil, 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 20, U.S. CENTCOM posted that U.S. forces have redirected 90 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 20 (Credit: U.S. CENTCOM/X)

CENTCOM also posted that U.S. forces interdicted the Iranian-flagged tanker CELESTIAL SEA (9397030) for attempting to breach the blockade by sailing toward an unnamed Iranian port.  This is the 91st ship redirected by U.S. forces. 

U.S. CENTCOM update on May 20 (Credit: U.S. CENTCOM/X)

CELESTIAL SEA has been on the UANI Ghost Armada blacklist since 2023, and sanctioned by OFAC since 2025.  It appears to have been interdicted off the coast of Oman.  It departed the Malaysian Easter Out of Port Limits (EOPL) anchorage area on April 18, sailing via the Malacca Strait into the Indian Ocean, where is conducted some unusual maneuvers south of Sri Lanka on April 30, before crossing the Arabian Sea toward the Gulf of Oman, where it was interdicted today.

Interdicted tanker on May 20 (Credit: Marine Traffic)

Status of the Strait of Hormuz

The Strait of Hormuz remains a critical flashpoint in the Iran War. Since the start of the conflict, 43 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.

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

UANI has identified at least 64 tankers laden with Iranian oil — primarily crude — 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 20

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 16, 11 Iran-flagged tankers, as well as three Ghost Armada 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.

Number of Iranian Loadings

Since the outbreak of the conflict, UANI has tracked at least 74 Iranian oil loadings, 41 of which originated from Kharg Island, Iran. These shipments represent approximately 83 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 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 19, five Iran-flagged tankers, all unladen, plus one UANI Ghost Armada tanker carrying Iranian crude, were anchored near Galle. On the satellite image below, white squares denote Iran-flagged tankers, and the white circle denotes the Ghost Armada vessel. 

Iran linked tankers anchored near Galle, Sri Lanka on May 19 (Credit: ESA Copernicus)

On May 20, the Iran-flagged tanker SARAK (IMO 9226968) appeared on AIS, sailing northeast from the vicinity of Galle, Sri Lanka, in the Indian Exclusive Economic Zone (EEZ).  SARAK was last observed on May 10, in the Malacca Strait after departing the Malaysian Eastern Out of Port Limits (EOPL) anchorage on May 8.   

Iran flagged tanker near Sri Lanka on May 20 (Credit: Marine Traffic)

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. 

The Iran flagged tanker TOUR 2 (IMO 9364112), also known as KARIZ, departed the anchorage south of Hong Kong on May 18, still reporting laden. It is now drifting in waters about 100km southeast of Hong Kong.  The tanker had previously departed the EOPL, despite being anchored there for over two weeks, reporting laden and broadcasting its AIS, and transited the South China Sea northbound on May 11. This is an unusual pattern of movement for an Iran flagged OFAC-sanctioned tanker.

Iran flagged tanker departing the EOPL on May 19 (Credit: Marine Traffic)

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-flagged DERYA (IMO 9569700) departed the EOPL anchorage and transited the Singapore and Malacca Straits, reporting empty with a destination of Colombo, Sri Lanka on May 18, but has not been observed since then. DERYA had previously been the feeder in an STS transfer of Iranian crude in the EOPL on May 14. Like HUGE, DERYA also took the uneconomical route through the Indian Ocean and the Lombok Strait in order to avoid interdiction by U.S. naval forces. DERYA had previously appeared in the Gulf of Kutch, attempting to deliver Iranian oil at Sikka, India but departed on April 19.

DERYA transited Southeast Asian sea lanes on May 18 (Credit: ESA Copernicus)

Iran-Oil Laden Tankers off the Malaysian Coast

From February 28, the start of the conflict, to today, UANI has recorded 43 STS transfers of Iranian oil 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 20, 36 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 30 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. This has contributed to increased instances of ships pausing and waiting in clusters at anchorages across the region.

Iran flagged cargo vessels across the Indo-Pacific on May 20 (Credit: Marine Traffic)

The Iran flagged, OFAC sanctioned container ship VELON 1 (IMO 9122473) continued sailing the Arabian Sea, however, it began reporting on AIS that it is “Not Under Command”.  On May 19, VELON 1 stopped and began drifting for unknown reasons, but is underway again. 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 and that it will arrive at Port Klang, Malaysia on May 29.

Iran flagged container ship in the Gulf of Aden on May 20 (Credit: Marine Traffic)

On May 20, there were no significant changes to the multiple Iranian flagged tankers and cargo vessels that continued to anchor offshore of Karachi, Pakistan. ARIES (IMO 9369722), MAHNAM (IMO 9213387), DELRUBA (IMO 9305207), WARTA (IMO 9465849),and PARNIA (IMO 9167265) were openly broadcasting on AIS while anchored about 70km offshore. The tankers STREAM (IMO 9569633), HERBY (IMO 9362059) and SOBAR (IMO 9221970) are also anchored nearby, outside territorial waters. Finally, the container ship TOUSKA (IMO 9328900) was anchored just 16 km outside Karachi port, inside Pakistani territorial waters. All of these Iran flagged vessels are OFAC sanctioned.  At least 8 other non-Iranian flagged Ghost Armada tankers are also anchored in the Pakistan EEZ.

Iran flagged cargo vessels near Karachi, Pakistan on May 20

(Credit: Marine Traffic and ESA Copernicus)

On May 20, the Iran flagged container ship ARTABAZ (IMO 9283007), was still drifting in the Arabian Sea approximately 200 km offshore of the Indian Coast, in the Indian Exclusive Economic Zone (EEZ). ARTABAZ departed Mumbai on April 19, after unknown cargo operations. It is possible that the ARTABAZ is loitering in this area conducting maritime surveillance in a picket pattern, as this is a highly unusual behavior for a container ship transporting routine cargo. 

Iran flagged container ship drifting in Arabian Sea on May 20 (Credit: Marine Traffic)

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 over three weeks since it conducted unknown cargo operations in Kandla Terminal from April 18-19. 

Iran flagged container ship anchored in Gulf of Kutch on May 20

(Credit: Marine Traffic and ESA Copernicus)

The OFAC sanctioned, Iran flagged bulk cargo ship BAHJAT (IMO 9405954) got underway from the anchorage off Galle, Sri Lanka, and began sailing east.  It is reporting a ballast condition, but not listing any destination for this new voyage.  It had been anchored off Galle since May 6.  On May 19, the Iran-flagged tanker DOWNY (IMO 9218480) briefly appeared on AIS in the Galle Outer Port Limits (OPL) anchorage. Three other Iran-flagged tankers — HAWK (IMO 9212890), HALTI (IMO 9212890), and HELM (IMO 9357391) — were observed in satellite imagery at Galle OPL on May 19, although they not broadcasting on AIS. And the Iran-flagged tanker SARAK (IMO 9226968) appeared on AIS, today, sailing northwest form the vicinity of Sri Lanka.

Iran flagged ships near Sri Lanka on May 20 (Credit: Marine Traffic and ESA Copernicus)

On May 20, the OFAC-sanctioned Iran flagged bulk cargo ship KIAZAND (IMO 9465758) remained in an anchorage off Phuket, Thailand. The vessel departed Songkhla, Thailand on May 14 and passed the Singapore Strait on May 16. KIAZAND conducted unknown cargo operations from May 3-8, in port Songkhla, before anchoring offshore Songkhla from May 8-14 and is now reporting that it is in ballast condition.

Iran flagged cargo ship in Gulf of Thailand on May 20 (Credit: Marine Traffic and ESA Copernicus)

On May 20, the Iran flagged general cargo ship AREZOO (IMO 9165786) and containership RADIN (IMO 9820257) continued to remain anchored off Port Klang, Malaysia, inside Malaysian territorial waters. The Iran-flagged container ship AZARGOUN (IMO 9283019) which departed the Malaysian EOPL on May 19, briefly stopped at the Port Klang anchorage near ARESZOO and RADIN, before continuing north in the Malacca Strait. AZARGOUN is reporting its destination as Chennai, India, with an ETA of May 26.   All these vessels are sanctioned by OFAC.

Iran flagged container ships near Malaysia on May 20 (Credit: Marine Traffic)

Five Iran-flagged cargo ships remained anchored in the Malaysian EOPL anchorage area, openly broadcasting on AIS on May 19: the bulk cargo ships ARVIN (IMO 9193202), MIAMI PRIDE (IMO 9274941), BASKAR (IMO 9405942) and ANDIA (IMO 9193197) and the container ship OURA (IMO 9387815). These vessels are likely waiting in the EOPL due to the U.S. blockade.

Iran flagged cargo ships at Malaysian EOPL on May 20 (Credit: Marine Traffic and ESA Copernicus)

Two Iran-flagged container ships SHABDIS (IMO 9349588) and SHABGOUN (IMO 9346524) remain anchored in the vicinity of Zhuhai. SHABGOUN. The Iranian flagged tanker, TOUR 2 (IMO 9364112), also known as KARIZ, appeared on AIS south of Hong Kong on May 18, and is currently drifting about 100 km southeast of Hong Kong island. It is reporting on AIS that it is laden. All of the vessels are OFAC sanctioned.

Iran flagged container ships at Zhuhai, China, on May 20 (Credit: Marine Traffic)

On May 20, the Iran-flagged container ship BEHTA (IMO 9349590) arrived at Chang Jiang Kuo (CJK) anchorage outside of Shanghai.  It departed the port of Zhuhai on May 18.  The BEHNAVAZ (IMO 9346548) appeared to enter the port area of Shanghai, although it appeared to stop broadcasting on AIS, as it entered the inbound channel form the CJK anchorage area. 

Iran flagged container ships near Shanghai, China, on May 20 (Credit: Marine Traffic)