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Update: 'tanker war' reintensifies with two incidents in a week
Tensions in Middle East shipping lanes initially escalated after the US unilaterally pulled out of the joint comprehensive plan of action (JCPOA) nuclear treaty in 2018 and reimposed sanctions on Iran. Throughout 2019, a series of tit-for-tat measures involving tanker seizures and a diplomatic standoff between the US, UK, Iran, Russia and other states affected commercial shipping in the region. Below, a regularly updated timeline chronicles the hostilities and their impact on tanker shipping in the Middle East Gulf in 2021.
Of late, a tanker was reportedly boarded by hijackers in Gulf of Oman and told to sail to Iran. The incident came within a week of a deadly attack in which two crewmembers on board tanker Mercer Street were killed by an explosive-laden drone strike that the US and UK claimed was initiated by Iran
2021:
4 August: Tanker boarded by hijackers in Gulf of Oman reportedly told to sail to Iran
- The incident was first reported by the UK Maritime Trade Operations (UKMTO) security monitoring service on 3 August as a ’potential hijack’ with no vessel named.
- Security firm Dryad Global tweeted "unconfirmed reports involving the vessel Asphalt Princess off Fujairah" in the United Arab Emirates, saying an Omani Royal Air Force aircraft had responded.
- UKMTO tweeted that the incident was "complete" on 4 August, saying "Boarders have left the vessel. Vessel is safe."
- The BBC, citing unnamed sources, said the vessel had been boarded by armed men who ordered the ship to sail to Iran. The UK media outlet also said unnamed analysts suspected Iranian forces were behind the aborted hijacking.
- Iran has denied involvement in recent attacks.
- Shipping asset tracking firm VesselsValue lists Asphalt Princess as a 9,700-dwt small dirty (product) tanker, fully laden.
30 July: US and UK blame Iran for attack on Israeli-operated tanker Mercer Street
- Mercer Street was attacked off the coast of Oman on 29 July; the attack killed two crew members on board, one a British citizen, the other Romanian.
- Isreal’s prime minister and officials in the US and UK Governments laid the blame for the attack on Iran.
- UK Foreign Secretary Dominic Raab said the UK Government suspected one or more drones were used in what it called a "deliberate, targeted" attack that was a "clear violation of international law".
- US Secretary of State Antony Blinkin said "an appropriate response" would be taken.
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IMO Secretary-General Kitack Lim "noted with great concern the attack on the Liberia-flagged oil tanker Mercer Street off the coast of Oman during the night of 29 to 30 July 2021 and condemns the attack in the strongest terms.
- BBC News linked the attack to "an undeclared ’shadow war’ between Israel and Iran".
- Iran has denied involvement in the incident.
- Mercer Street’s Israel-owned ship operator Zodiac Maritime released short statements regarding the incident:
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We can confirm that there has been a suspected piracy incident on board the product tanker Mercer Street. The ship is a Japan-owned vessel managed by our UK-based Zodiac Maritime Office. At the time of the incident the vessel was in the northern Indian Ocean, travelling from Dar es Salaam to Fujairah with no cargo on board. We are in co-ordination and liaising with the UK MTO and other relevant authorities.
- With profound sadness, we understand the incident onboard Mercer Street on 29 July 2021 has resulted in the deaths of two crew members on board: a Romanian national and a UK national. We are not aware of harm to any other personnel.
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We can now confirm that the Mercer Street is sailing under the control of its crew and under its own power at 14 knots to a safe location with a US naval escort.
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9 April: Iran releases seized South Korean tanker Hankuk Chemi
- South Korea’s Foreign Ministry has confirmed the safe release of 17,400-dwt, South Korea-flagged tanker Hankuk Chemi which was detained by Iran’s Islamic Revolutionary Guard Forces in January over an alleged dispute involving pollution, and shortly after Iran reportedly had assets frozen by South Korean banks.
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"The detention of a Korean national ship and the captain of the ship, which was detained by Iranian authorities on 4 January 2021 and anchored at Rajai Port near Bandar Abbas, Iran, was lifted today. It was confirmed that the master and crew are in good health, and there is no abnormality in the ship’s overall condition, such as cargo. After completing local administrative procedures, the ship departed safely... at Iranian local time 05:50."
5 January: South Korea delegation to negotiate for tanker’s release
- Britain’s BBC reports that South Korea will send a delegation to Iran "at the earliest possible date" to try to negotiate the release of the tanker seized by Iran’s Revolutionary Guards. The BBC report said the tanker operators deny allegations of pollution.
- Iran’s Tasmin news agency reports that a "Korean foreign ministry official met with Iranian top envoy in Seoul on Tuesday to discuss yesterday’s seizure of a South Korean tanker in the Strait of Hormuz over technical issues".
- Multiple news outlets report Iranian Government denials that the seizure is a form of hostage-taking linked to Iranian funds reported to be US$7Bn being held by South Korea.
4 January: Iranian forces seize South Korea-flagged tanker
- Following another escalation in tensions between the US and Iran, security firms including UKMTO, Dryad Global and Ambrey Intelligence report an incident involving 17,400-dwt, South Korea-flagged tanker Hankuk Chemi being diverted under escort into Iranian waters.
- State-linked Iranian news outlets including television and online publications confirm the tanker’s detention, along with allegations of "environmental pollution".
- VesselsValue website, tracking vessels and their market values, shows Hankuk Chemi’s position in the Strait of Hormuz in the vicinity of the Iranian port of Bandar Abbas and lists Nordic Tankers as the vessel’s operators.
- Associated Press reports that Iran restarts 20% uranium enrichment.
2020:
6 January: British warships sent into the Middle East Gulf to protect UK-flagged tankers
- Following the US drone strike that killed Iranian Quds Force commander Qasem Soleimani on 3 January 2020 in Baghdad, the UK Government has ordered the warships HMS Norfolk and HMS Montrose into the Straits of Hormuz. Their remit is to protect UK-flagged tankers from any possible retaliatory attacks from Iranian forces or its proxies.
21 January: EU nations back naval patrol in Strait of Hormuz
- Eight EU members have promised political backing for a naval initiative that aims to assist civilian vessels in the Middle East shipping lane and to ’de-escalate’ tensions in the region
30 November: Spate of tanker-related incidents on the rise in Middle East waters
03 December: The risks of trading in the Middle East remain of real concern
14 December: Hafnia tanker hit by explosion in Jeddah
2019:
12 May: Four oil tankers suffer explosions while at anchor off the coast of Fujirah, UAE
13 June: Front Altair and Kokuka Courageous are hit by explosions in the Gulf of Oman
Read more of our overage on the re-emergence of ’tanker wars’ in the Middle East:
- Governments ’concerned’, shipowners condemn apparent ’co-ordinated attacks’ on tankers
- Saudi Arabia reports attacks on two of its tankers
- Impact on tanker trade when Trump waves away Iran sanction waivers
- Five reasons behind the muted market reaction to the US leaving the Iran nuclear deal
3 July: Gibraltar names Grace 1 in “Specified Ship Notice”
- The notice requires Grace 1’s detainment for up to 72 hours if the vessel enters British Gibraltar Territorial Waters (BGTW).
- Grace 1 enters BGTW just after midnight on 4 July, according to AIS data from VesselsValue. The data also shows Grace 1 delivering a cargo at Khor Fakhan in the United Arab Emirates in late January 2019, remaining at anchor there until mid-April when it was listed as “floating storage” before setting off in late May on a journey around Africa’s southern tip on its way to the Mediterranean, where it arrived laden.
4 July: Grace 1 detained in Gibraltar
- In the early morning hours, Gibraltar police and 30 of Britain’s Royal Marines board and detain the 300,600-dwt VLCC tanker Grace 1 and its cargo.
- Chief Minister of Her Majesty’s Government of Gibraltar, Fabian Picardo releases a video statement laying out what he calls the “reasonable grounds” for detaining the tanker, including the belief that the tanker was carrying its cargo of crude oil to Syria’s Baniyas Refinery, in breach of EU sanctions.
- Spain’s foreign minister Josep Borrell reportedly claims Gibraltar detained Grace 1 following a US request to Britain to seize the tanker.
- Iran summons Britain’s ambassador in Tehran over what Iranian foreign ministry spokesman Abbas Mousavi terms the “illegal seizure” of Grace 1.
5 July: Iran threatens British vessels
- Advisor to Iranian supreme leader Ayatollah Khamanei tweets “If Britain does not release the Iranian oil tanker, it is the authorities’ duty to seize a British oil tanker.”
- Iran accuses the UK of acting on “the order of the US” in seizing Grace 1.
- Gibraltar releases a statement saying “There has been no political request at any time from any Government that the Gibraltar Government should act or not act, on one basis or another.”
- Gibraltar Supreme Court orders Grace 1’s detention extended by a further 14 days citing “reasonable grounds” and compliance with EU sanctions against Syria.
6 July: Tanker changes course in Gulf
- News reports highlight British-flagged tanker Pacific Voyager “veering” off course, but United Kingdom Maritime Trade Operations explain the tanker was “adjusting its arrival time at the next port”.
7 July: Norwegian-owned tanker involved in May’s incidents in Fujairah returns to Iran
- After it was one of several tankers holed in incidents in the Strait of Hormuz in May, AIS data shows MR2 tanker Andrea Victory has returned, laden, to the Iranian port of Bandar Imam Khomeini.
8 July: BP oil tanker “shelters” in Middle East Gulf
- News reports claim BP Shipping-operated tanker British Heritage has “cancelled” a voyage to Iraq’s Basrah terminal to avoid sailing near to Iran’s coast, citing unnamed sources.
- Gibraltar releases a statement saying Grace 1 was detained when the vessel “freely navigated into BGTW… on a pre-arranged call for provisions and spare parts”.
- Gibraltar’s statement says it has confirmed Grace 1 is carrying a “full load of crude oil”.
9 July: UK military escort for Pacific Voyager
- Online ship data watchers spot what they believe to be a British warship or possibly two escorting British-flagged tanker Pacific Voyager on its voyage through the Strait of Hormuz.
10 July: UK military escort for British Heritage
- AIS website Marine Traffic shows BP-operated tanker British Heritage flanked by a UK warship escort approaching the Strait of Hormuz.
11 July: Iranian vessels attempt to seize British tanker
- BP-operated tanker British Heritage is reportedly approached by Iranian gunboats, which are seen off when British warship HMS Montrose turns its guns toward the boats.
13 July: UK Ministry of Defence (MoD) to send second warship to Gulf
- Already having sent HMS Montrose to the Middle East Gulf to protect commercial trade, HMS Duncan, a Type 45 destroyer, is to be deployed with the aim of being in the Gulf region by next week.
- IRNA reports the MoD and UK’s ambassador to Iran saying the vessel is replacing others and not a part of any international maritime coalition proposed by the US.
13 July: UK-Iran talks offer possibility for Grace 1’s release
- UK Foreign Secretary Jeremy Hunt tweets that the UK would facilitate the release of Grace 1 if Iran could offer assurance the vessel was not destined to deliver its cargo to Syria.
- "Just spoke to Iranian Foreign Minister Zarif. Constructive call. I reassured him our concern was destination not origin of the oil on Grace 1 and that UK would facilitate release if we received guarantees that it would not be going to Syria, following due process in [Gibraltar] courts. Was told by FM Zarif that Iran wants to resolve issue and is not seeking to escalate. Also spoke to Fabian Picardo who is doing an excellent job co-ordinating issue and shares UK perspective on the way forward.”
14 July: Clean product tanker Riah disappears from AIS tracking in Strait of Hormuz
- Riah, a 30-year old, 1,900-dwt bunkering tanker listed under UAE-based Prime Tankers disappears from AIS tracking near Larak Island, which lies in Iranian territorial waters in the Strait of Hormuz.
- The Panamanian-flagged vessel reportedly did not send a distress call, according to Emirati officials, who deny the ship is UAE-owned.
- The Iranian Foreign Ministry says Iran’s Islamic Revolutionary Guard picked up an SOS signal from a foreign-flagged oil tanker in the Middle East Gulf and brought it to Iranian waters for repair.
18 July: IRGC claim to have seized an oil tanker in Strait of Hormuz
- Iran’s Islamic Revolutionary Guard Corps Navy says it seized a ’foreign’ oil tanker on 14 July, in the Middle East Gulf with 12 crew on board, alleging that the ship was smuggling 1M litres of fuel.
18 July: Gibraltar and Iran confirm talks in London
- Gibraltar’s Chief Minister Fabian Picardo holds a meeting in London with Iranian officials to discusss Grace 1’s detention and "to seek to de-escalate" issues surrounding the detention.
19 July: Gibraltar’s Chief Minister reports on talks to UK Parliament
- Chief Minister Fabian Picardo gives a statement to parliament to summarise his meeting in London with Iran’s Foreign Minister Javad Zarif and other officials
- "We discussed with our Iranian interlocutors matters related to the detention of Grace 1," Mr Picardo said. "At every stage we emphasised the distinct nature of Gibraltar’s jurisdiction and the independence of the Supreme Court of Gibraltar as well as the importance of the due process of law being followed in a state governed by the rule of law."
19 July: Gibraltar’s Supreme Court extends Grace 1 detention
- The Government of Gibraltar released a statement saying, "a private meeting of the Supreme Court on an application by the Attorney General, the Court has extended the period of detention of the vessel, Grace 1, for a further 30 days and has set a new hearing for 15 August 2019".
19 July: Iran’s Islamic Revolutionary Guard board British-flagged tanker
- Iran’s Islamic Revolutionary Guard forces board MR2 product tanker Stena Impero.
- A statement from the military force said the tanker "was confiscated by the Revolutionary Guards... for failing to respect international maritime rules".
- Video posted online shows Iranian Revolutionary Guard forces rappelling from helicopters to the ship’s deck in the Strait of Hormuz.
- Audio from the moments leading up to the incident has also emerged, posted to the Twitter feed of security risk management firm Dryad Global. The VHF audio purports to feature an Iranian coast guard authority telling a British naval officer on board HMS Montrose, which is patrolling the area, "I want to inspect the ship for security reasons".
- Stena Bulk and Northern Marine Management confirm that Stena Impero is in Iranian hands: “Stena Bulk and Northern Marine Management can confirm that at approximately 1600 BST on 19 July UK-registered vessel Stena Impero (built 2018, 49,683 dwt) was approached by unidentified small crafts and a helicopter during transit of the Strait of Hormuz while the vessel was in international waters. We are presently unable to contact the vessel which is now heading north towards Iran.
31 July: Iran’s Islamic Revolutionary Guard claim to have detained another tanker
- Iranian television news claims that the Islamic Revolutionary Guard forces have detained a "tanker", which it accuses of smuggling fuel to Arab countries.
- Images shown on Iranian television of the detained vessel appear to show an elderly offshore support vessel (OSV), possibly a platform supply vessel, as opposed to a tanker.
- The unnamed vessel was said to be carrying 700,000 litres of fuel and has purportedly been taken to a port in southern Iran.
- Reports claim the vessel was Iraqi, but Iraqi authorities deny the connection.
5 August: UK joins US in ’maritime security mission’ in Middle East Gulf
- The UK’s Ministry of Defence announces it is "reaffirming its commitment to freedom of navigation and safe passage through the Gulf by playing a leading role in a new international maritime security mission".
- Royal Navy and US naval vessels will work together, drawing on "assets already in the region to increase inter-state maritime co-operation", a statement from the MoD said.
- "This new co-ordinated effort will bolster the work the UK has already being undertaking to this end, including through HMS Duncan and HMS Montrose accompanying UK-flagged ships. At the same time, the Government remains committed to working with Iran to reduce the current tensions and to the Iranian nuclear deal as the best means of preventing a nuclear-armed Iran," the statement said.
5 August: Iran and Russia pledge joint naval exercises in Middle East Gulf
- Iran’s state-run PressTV reports Iranian Navy Rear Admiral Hossein Khanzadi saying a "classified" agreement to expand military co-operation with Russia will include joint military drills in the Middle East Gulf before the end of 2019.
6 August: Iran’s president claims the Strait of Hormuz is closed to UK vessels
- In a speech broadcast live on Iranian state television, president Hassan Rouhani issues a threat to UK shipping. According to translations in western media, Mr Rouhani said “Peace with Iran is the mother of all peace; war with Iran is the mother of all wars... A strait for a strait. It cannot be that the Strait of Hormuz is free for you and the Strait of Gibraltar is not free for us.”
8 August: US says Iran is spoofing commercial shipping GPS in Strait of Hormuz
- The US Department of Transportation’s Maritime Administration (MARAD) issues a new advisory suggesting Iran is interfering with ships’ GPS systems as they transit the Strait of Hormuz.
- "Heightened military activity and increased political tensions in [the Middle East Gulf] region continue to pose serious threats to commercial vessels. Associated with these threats is a potential for miscalculation or misidentification that could lead to aggressive actions. Vessels operating in the [Middle East] Gulf, Strait of Hormuz, and Gulf of Oman may also encounter GPS interference, bridge-to-bridge communications spoofing, and/or other communications jamming with little to no warning," the advisory says.
11 August: Stena Bulk CEO asks Indian Prime minister to help free Stena Impero crew
31 August: US Secretary of State claims Adrian Darya 1 is headed to Syria
- US Secretary of State Mike Pompeo tweets that the tanker is underway to Tartus, Syria:
FM @JZarif guaranteed to the UK that the IRGC oil tanker #Grace1 / #AdrianDarya1 would not head to Syria. We have reliable information that the tanker is underway and headed to Tartus, Syria. I hope it changes course. It was a big mistake to trust Zarif. pic.twitter.com/ZJ06MWjvCO
— Secretary Pompeo (@SecPompeo)FM @JZarif guaranteed to the UK that the IRGC oil tanker #Grace1 / #AdrianDarya1 would not head to Syria. We have reliable information that the tanker is underway and headed to Tartus, Syria. I hope it changes course. It was a big mistake to trust Zarif. pic.twitter.com/ZJ06MWjvCO
— Secretary Pompeo (@SecPompeo) August 30, 2019
2 September: Adrian Darya 1 AIS position lists vessel off Lebanon coast, fully laden
- After a slow transit through Syrian waters on 1 September, VesselsValue’s ship tracking software shows the tanker off the coast of Lebanon and lists the vessel as fully laden, which could mean the vessel has not managed to offload its 2.1M barrels of crude oil via ship-to-ship transfer. Adrian Darya 1’s AIS now lists a port in Kuwait as its final destination. The Kuwaiti port, Mina Al Ahmadi, does have an oil terminal; however Kuwait’s close historic ties with the US and the current sanctions against the vessel would make the port an unlikely destination for Adrian Darya 1.
3 September: Adrian Darya 1 goes dark on AIS off Syria’s coast
- According to VesselsValue tracking data, Adrian Darya 1’s last AIS check-in is listed at 16:54 on Monday, 2 September, off the cost of southern Syria, heading north.
- There is a Russian naval centre in Tartus, in Syria’s southern region near where Adrian Darya 1 was transiting when its AIS went dark. Not far to the north of Tartus is the Baniyas oil refinery and terminal.
4 September: Iran says it will release seven Stena Impero crew
- An Iranian foreign ministry spokesman announces on state television that seven crewmembers from the impounded British vessel Stena Impero would be set free.
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Stena Bulk, which operates the vessel, releases a statement saying it understands the release is underway but cautioning it has not received confirmation of a release date directly from the Iranian authorities.
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Erik Hanell, President and CEO, Stena Bulk said: We are very pleased that for seven crewmembers their ordeal may soon be over, and they may return to their families, however we cautiously await official confirmation of their release date. We view this communication as a positive step on the way to the release of all the remaining crew, which has always been our primary concern and focus.
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According to Stena, 16 crewmembers will remain on board satisfying the vessel’s Minimum Safe Manning Certificate (MSMC).
4 September: US offers ’up to US$15M for anyone helping ’disrupt’ IRGC operations
- A statement from the US state department says, "The US Department of State’s Rewards for Justice (RFJ) is offering a reward of up to $15 million for information leading to the disruption of the financial mechanisms of Iran’s Islamic Revolutionary Guard Corps (IRGC) and its branches, including the IRGC-Qods Force (IRGC-QF). This includes seeking information on the IRGC’s illicit oil sales, including via oil tankers like the Adrian Darya."
4 September: US confirms ’outreach’ to tanker captain after report of cash offer
- The US state department offered millions of dollars to the captain of Iranian tanker Adrian Darya 1, it confirmed after the Financial Times reported the move.
- Brian Hook, head of the state department’s Iran Action Group, reportedly emailed the tanker captain to try to convince him to sail the vessel somewhere the US could seize it.
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A US government spokeswoman told AFP news agency "We have conducted extensive outreach to several ship captains as well as shipping companies."
5 September: Iran releases seven Stena Impero crewmembers
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Stena Bulk President and CEO Erik Hanell says his company "can confirm that seven crew members of the Stena Impero have been released and are now travelling to a safe location where they will be reunited with their families". "They will receive medical checks and a debriefing before being repatriated to their home countries at the earliest opportunity," Mr Hanell said.
23 September: Iran claims Stena Impero is ’free to go’
- Iranian government spokesman Ali Rabiei has said "the conditions for letting the oil tanker go free have been fulfilled and the oil tanker can move", according to Iran’s official IRNA news agency.
- The British-flagged tanker was set to move from the port of Bandar Abbas to international waters, according to an IRNA report quoting Allah Morad Afifi Pour, managing director of Hormozgan Ports and Maritime Organization.
- Stena Bulk said no timeline for the vessel’s release had yet been communicated, and the vessel’s AIS positioning system shows it stationary near the port of Bandar Abbas.
24 September: Stena Bulk confirms vessel has not yet left Iranian waters
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A statement from Stena Bulk CEO Erik Hanell says “Despite public statements by Iranian authorities over the past three days that judicial proceedings have concluded, and the Stena Impero is free to leave Iran, the vessel remains detained at anchor in Bandar Abbas.We continue to work hard to secure the release of the crew and vessel."
27 September: Stena Bulk confirms Stena Impero and its crew are en route to Dubai
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A statement from Stena Bulk chief executive Erik Hanell confirms that, after being held for 70 days, Stena Impero has been set free.
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“Stena Bulk and Northern Marine Management confirm Stena Impero and its crew have been released," Mr Hannel wrote.
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Stena’s CEO said the vessel has left the port of Bandar Abbas and is transiting to Dubai for the crew to disembark and receive medical checks and de-briefing.
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“The families of crew members have been informed and the Company is currently making arrangements for the repatriation of its valued seafarers at the earliest possible opportunity,” he said.
9 October: US Secretary of State Mike Pompeo says Adrian Darya cargo went to Syria
- US Secretary of State Mike Pompeo tweets images purportedly showing a ship-to-ship transfer, in his words, ’proving Iran lied to the UK’.
Oil from the #AdrianDarya1 has been offloaded in Syria, proving that Iran lied to the UK and Gibraltar. This terrorist oil will fund Assad’s war and Iran’s sectarian violence. EU members should condemn this action, uphold the rule of law, and hold Iran accountable. pic.twitter.com/4GPZpdYU8b
— Secretary Pompeo (@SecPompeo)Oil from the #AdrianDarya1 has been offloaded in Syria, proving that Iran lied to the UK and Gibraltar. This terrorist oil will fund Assad’s war and Iran’s sectarian violence. EU members should condemn this action, uphold the rule of law, and hold Iran accountable. pic.twitter.com/4GPZpdYU8b
— Secretary Pompeo (@SecPompeo) October 9, 2019
- The images came from satellite imagery firm Maxar and one is reproduced in this report, with their permission.
Satellite image ©2019 Maxar Technologies.
11 October: Iranian tanker reportedly hit by explosions off Saudi coast
- NITC claims one of its tankers has been hit by ’rocket attacks’ and suffered explosions. To read the full story, click above or here.
Editor’s note: this article is updated as events unfold. The original article was published on 11 July 2019, following reports from the British Government that BP-operated tanker British Heritage had been approached by Iranian vessels in the Strait of Hormuz.
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