More than a million US crude contracts were traded during the session, as a three-year agreement between OPEC and Russia turned into a difference.
Brent crude futures recorded the largest daily decline in percentage terms since December 2008, to drop by $ 4.72 or 9.4% and to settle at $ 45.27 a barrel. This is the lowest closing level for Brent since June 2017.
US West Texas Intermediate crude fell $ 4.62, or 10.1%, to $ 41.28 a barrel, the lowest closing level since August 2016 and the biggest daily loss in percentage since November 2014.
More than 4.58 million US crude contracts were traded for the month of the earliest maturity this week, and it is the most intense weeks for the volume of trading that contract at all.