Iran has released six supertankers from its fleet of vessels storing crude oil, a 40% reduction that may mean more oil heading to Europe, Bloomberg has reported, citing tracking data. According to data from the ships collected by AISLive, rhe National Iranian Tanker Co has nine supertankers stationed off the UAE and its own coast, down from 15 of the vessels on April 27. The six tankers that have been released can hold about 12 million barrels of oil.