The Tuesday report by Reuters news agency said no company has been willing to lighter crude oil cargo aboard Suez Rajan, a Marshall Islands-flagged tanker that has been anchored off Galveston, about 50 miles (80 km) outside of Houston, since May 30.
The report added a main reason for the ship to be unable to unload is because commercial agents fear that any vessel that takes the cargo will be shunned by customers in future voyages.
However, it quoted an unnamed industry expert as saying that shipping agents avoid lightering the tanker out of fear of repercussions from Iran.
Iranian authorities have warned in the past that the country would retaliate against any oil company unloading Iranian oil that is illegally seized by another country.
Commander of Islamic Revolution Guards Corps Navy Rear Admiral Alireza Tangsiri said last week that Iran would take action against the US if it allows the discharge of the Iranian oil cargo off the Texas coast.
The deputy commander of Iran’s Islamic Revolution Guards Cords (IRGC) said on Tuesday the country will act in kind if the United States empties the cargo of an Iranian tanker that it has illegally seized to use or sell.
Iranian authorities have previously designated attempts by the US to seize Iranian oil through enforcing court orders in other countries as an act of piracy.
Tehran has used its political and military capacities to prevent previous US attempts to seize its oil shipments.
The inability of the Suez Rajan to unload after eight weeks of sitting off the US coast comes as the vessel has secured the necessary US approvals and paperwork for doing so, said the report by Reuters.