Iran’s newly established Persian Gulf Strait Authority (PGSA) published the “non-compliant vessels” list over the weekend, accusing the ships of breaching its arrangements for passing through the strategic waterway.   The authority also warned that vessels carrying out ship-to-ship transfers, transhipment or other operations with listed ships would be added to the blacklist. Owners seeking removal must apply to Iran’s maritime authorities and provide an explanation.     The list covers VLCCs, product tankers, LNG and LPG carriers, containerships and bulkers linked to some of the industry’s best-known names, including ADNOC Logistics & Services and its Navig8 subsidiary, Bahri, Sinokor, Stolt-Nielsen, Klaveness Combination Carriers, Shipping Corporation of India, Dynacom and GasLog.      ADNOC L&S has the largest exposure, with eight directly managed vessels on the list. Sinokoris linked to at least five ships, while three vessels are connected to Saudi state owner Bahri.      Iran published 46 entries, but only 45 individual ships are involved. The tanker Vadin appears twice under the same IMO number, with its former name Lila Vadinar also included.      At least 14 of the listed vessels have already been attacked in and around Hormuz in recent months. They include Nakilat’s Al Rekayyat, Bahri’s Wedyan, the Sinokor-linked Cyprus Prosperity, ADNOC-operated Al Bahyah and Mombasa B, Stolt Nielsen’s StoltMagnesium and the AD Ports-controlled containership GFS Galaxy.          The PGSA did not specify what each vessel had done to breach the rules. Tehran has previously demanded that ships obtain Iranian clearance and pay for navigation, security, insurance and other services before crossing the strait. An Iranian parliamentary committee has also approved draft provisions allowing fees to be charged for navigation, environmental, bunkering, insurance and safety services.

The measures leave owners facing conflicting demands from Tehran and Washington. The US sanctioned the PGSA in May, accusing the IRGC-backed organisation of running an extortion scheme against commercial shipping.

In updated guidance issued on Monday, the US Office of Foreign Assets Control warned that US and non-US companies could face sanctions merely for accepting services or responding to information requests from the PGSA, even where no payment changes hands.       The guidance was accompanied by a broader Treasury offensive that expanded potential secondary sanctions to shipping and four other sectors. Nearly 60 Iran-linked companies, individuals and vessels were targeted, including five shadow-fleet ships accused of moving Iranian oil and petroleum products: Sifra, G Silver, Quantum Hope, Voyage Elite and Tela.      Analysts at SEB said the larger escalation was the sector-wide shipping designation and its secondary-sanctions reach. The move gives Treasury scope to target Chinese buyers and shadow-fleet brokers moving Iranian barrels, while action against brokers and STS networks would be harder to route around than sanctions on individual hulls.      “This reinforces our China-to-Atlantic tonne-mile view, although designation is not enforcement. Seeing is believing until flows change,” the bank said.

US president Donald Trump had warned last week that countries providing Iran with any economic lifeline would face consequences. He specifically named ship registries alongside oil-smuggling networks, swap lines, cash transfers, exchange houses and front companies among the channels Washington wants shut down.      Meanwhile, UN secretary-general AntónioGuterres has called for support for a proposed confidence-building mechanism to keep essential cargoes moving through maritime chokepoints. The scheme would initially cover fertilisers and related raw materials, using ship registration and verification together with a deconfliction mechanism in Oman, with the option to expand it to other cargoes. The UN said the system could be deployed quickly but would require agreement from the countries involved.