LONDON, April 27 (Reuters) – Six tankers loaded with Iranian ⁠oil ⁠have been forced back to Iran ⁠by the U.S. blockade in recent days, ship-tracking data shows, underscoring the impact the ​Iran war is having on traffic through the Strait of Hormuz, a major global oil export route.

Between 125 and 140 ships ‌usually crossed in and out of ‌the strait daily before the U.S.-Israeli war on Iran began on February 28, but only seven have done so ⁠in the past ⁠day, according to Kpler ship-tracking data and satellite analysis from SynMax, and none ​carrying oil bound for the global market.

They included the Iranian-flagged dry bulk vessel Bavand which left from an Iranian port, and other vessels leaving from Iraqi ports, the data showed.

Iran has imposed restrictions on shipping using the strait, and the U.S. on April ​13 announced it would blockade Iran-related shipping. U.S. forces have turned back 37 vessels since then, the military ⁠said ⁠on April 25.

    The strait ⁠typically handles 20% of ​the world’s daily supply of oil and LNG. Activity has remained curtailed through it as talks between Iran ​and the United States remain stalled ⁠nearly two months into the war.

The U.S. military has not provided a complete breakdown of the type of ships it has diverted or the precise location of the interceptions. 

    “Iran has attacked and detained ships for not adhering to its required transit requirements, while the U.S. has continued to enforce its blockade,” ship broker Clarksons said in a note on Monday.

U.S. ⁠ALLOWED SOME VESSELS TO SAIL ON

    The six tankers forced to return to Iranian ports in ⁠recent days were carrying an estimated 10.5 million barrels of oil, according to satellite analysis from TankerTrackers.com.

While U.S. forces in the Gulf of Oman instructed some vessels to turn back, others appeared to be allowed to sail on. 

    Two tankers carrying around four million barrels of Iranian oil managed to sail past the blockade on April 24 bound for Asia, the data from TankerTrackers.com showed.   

Four separate, empty Iranian tankers were last seen around Pakistan’s coast after returning from Asia, according to analysis from TankerTrackers.com.    

    Analysts said U.S. forces have been diverting Iran-linked ships as far east as the Malacca Strait, so it is ⁠unclear whether those cargoes will reach buyers or be intercepted and redirected back to Iran.

Hundreds of ships and an estimated 20,000 seafarers remained stranded inside the Gulf.

    Those seafarers are “exposed to significant risks and considerable psychological strain,” Arsenio Dominguez, Secretary-General of UN shipping agency the International Maritime Organization, told a committee ​session on Monday. 

   “The longer this situation goes on, the greater the risk of serious accidents, ​including environmental accidents.”

(Reporting by Jonathan SaulEditing by Bernadette Baum)

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