By Nidhi Verma and Florence Tan

Aug 24 (Reuters) - Iran said it had blacklisted 45 tankers that had broken its rules for crossing the Strait of Hormuz, and would take action against any vessels ‌transferring loads with them, escalating its threats over the key waterway six months into the war.

The named ‌vessels could be fined, detained and have their cargoes confiscated, according to an X post late on Sunday from the Persian Gulf Strait ​Authority, a new body set up by Iran to manage the strait.

The warning was issued within days of the U.S. threatening Iran with "the toughest sanctions in history", and Iran saying its response to any new U.S. threats would be "devastating".

The restricted list includes very large crude carriers, liquefied natural gas and liquefied petroleum gas tankers, and clean product vessels, among others.

Some of ‌the named ships are owned by the ⁠United Arab Emirates' ADNOC Logistics and Shipping (ADNOC L&S), ADNOC's subsidiary Navig8 Tankers, and Saudi Arabia's national shipping carrier Bahri.

Any vessels involved in ship-to-ship transfers with the named vessels could be ⁠added to the blacklist, the Iranian X post added.

The post did not spell out what it meant by Iran's rules, but Tehran has in the past said ship-owners should get its clearance to transit the strait and said ships should pay for ​security and ​other services.

The U.S. has also imposed a naval blockade against ​Iran-related shipping.

The Gulf supplied about 20% of the ‌world's daily crude oil and liquefied natural gas before the Iran conflict disrupted tanker traffic.

U.S.-coordinated efforts to shuttle tankers quietly through the Strait of Hormuz to fill supertankers waiting just outside it are helping restore some of those export volumes.

U.S. Secretary of Energy Chris Wright said on X on Friday that the "7-day average of oil leaving the Strait is over 8 million barrels a day. Make no mistake, thanks to the U.S. Navy, oil is flowing through the ‌Strait of Hormuz."

Ships owned by Klaveness Ship Management, Stolt Tankers and ​South Korea's Sinokor were also included on the blacklist.

ADNOC declined to comment, ​while other shipping firms did not immediately respond ​to Reuters' requests for comment.

The Persian Gulf Strait Authority has said cargo owners should refer ‌to an updated list of vessels deemed non-compliant ​for voyages relating to the Gulf.

Ships ​seeking the removal of their names from the non-compliant vessels' list must submit a request with relevant explanations to Iran's maritime authorities, the post said.

Below is the list of vessels appearing in the non-compliance list.

No. Vessel ​Name IMO Number

1 Kiku 9329796

2 Mubaraz 9074626

3 Minoan Pioneer 9471630

4 Hafeet 9928009

5 Al Rekayyat 9397339

6 Wedyan 9524970

7 Cyprus Prosperity 9595216

8 Al Rawdah 9734513

9 Rasheeda 9443413

10 Lebrethah 9976927

11 Lila ‌Vadinar 9324100

12 Maha Roos 9231004

13 Gfs Galaxy 9401271

14 Al Bahyah 9937799

15 Mombasa B 9739501

16 Stolt Magnesium 9739317

17 Al Watan 9615030

18 Navig8 Messi 9482859

19 Singapore Prosperity 9419967

20 Disha 9250713

21 Gaslog Shanghai 9600528

22 Lubna 9489065

23 Hazi 1 7802598

24 Ryujin 8206818

25 Anna Barbara 9407500

26 Sunbird Arrow 9323821

27 Minoan Dignity 9294484

28 Maria 9917828

29 Kavomaleas 1042823

30 Mardan 9360453

31 Sweden Prosperity 9588392

32 Jarnain 9823546

33 Kaifan 9656046

34 Nissos Kea 9920758

35 Rotterdam Energy 9508859

36 Al ​Hamra 9074640

37 Umm Al Ashtan 9074652

38 Marigold Lng 9230062

39 Banastar 9228045

40 Navara 9241798

41 Nissos Heraclea 9419618

42 Blue Star 1 9215115

43 Ashley 9258466

44 Mraweh 9074638

45 Al Lulu 9583627

(Additional Reporting by Siyi Liu, Siddarth S and Enes ​Tunagur; Editing by Hugh Lawson, Thomas Derpinghaus and Andrew Heavens)