OPEC crude was sold at 77.11 dollars per barrel on Tuesday, down 1.9% from the previous day, the Vienna-based oil group reported on Thursday.
With this decline, the price of the reference barrel of the Organization of Petroleum Exporting Countries (OPEC) -a basket of fifteen types of crude oil, one from each member state- has fallen back to the level it had in mid-September.
Yesterday's marked cheapening, which was even more pronounced in other types of crude, such as Brent and Texas Intermediate Oil (WTI), has been attributed by analysts to signals sent by Saudi Arabia that the kingdom is willing to open the spigots to compensate for an eventual drop in Iran's supply.
The fear of a possible shortage as a result of the sanctions imposed by the United States to Tehran that will enter into force on November 4 has been driving the prices upwards in recent weeks, to levels that had not been seen in four years.
The OPEC barrel reached a peak of 84.09 dollars on October 4, almost 7 dollars more than its current price.