Brent crude oil plunged more than $6 a barrel on Thursday, the sharpest one-day fall since 2011, after OPEC decided not to cut production despite a huge oversupply in world markets. Oil prices have fallen by more than a third since June as increasing production in North America from shale oil has overwhelmed demand at a time of sluggish global economic growth.
Ministers from the Organization of the Petroleum Exporting Countries had been discussing at their meeting in Vienna whether to agree a production cut in an attempt to rebalance the global oil market. Asked whether the oil producer group had decided not to reduce production, Saudi Arabian Oil Minister Ali al-Naimi told reporters: "That is right."
Benchmark Brent futures were down by $4.75 a barrel at $73.00 by 1640 GMT, after hitting a four-year low of $71.25 a little earlier in the session. The contract was on track for its biggest monthly fall since 2008. U.S. crude was at $68.90, down $4.79, after hitting its lowest point since May 2010 at $67.75.