Iranian oil tanker operator NITC has at least two supertankers anchored off its coast for more than a month storing oil, one more than the previous month, according to Reuters calculations yesterday. The draught measurements of the two very large crude carriers (VLCC) indicated they were fully loaded with cargo, according to Reuters Freight Views. It was not clear if the ships are carrying crude, fuel oil or other products. Oil trade with Iran has become challenging as banks hesitate to provide financing due to tough international sanctions against the Opec member, industry sources say. Article continues below Iran is a major oil exporter and its production is equal to more than 4 per cent of daily world demand. Below are the where-abouts of 23 vessels owned by NITC. The privately held firm also charters ships from other shipping companies to transport and store oil. Volume is in deadweight tonnes (DWT), and the ship\'s draught is measured in metres. A VLCC draught measuring 19 metres or above typically indicates it is fully loaded with oil, while a draught below ten metres indicates no substantial cargo on board. A draught of around 15 metres for suezmaxes and 13 for aframaxes indicates a fully loaded ship.