Oil prices hit a four-year low in the wake of the decision by the Opec producers’ cartel not to cut output.
Brent crude touched a new four-year low of $71.12 a barrel early on Friday, before recovering to trade above $73.
The price of Brent had dived by more than $5 a barrel on Thursday after Opec announced no change to its production plans following a meeting in Vienna.
The 12 Opec members decided to maintain production at 30 million barrels per day, as first agreed in December 2011.
The price of US oil fell to $67.75 a barrel – the lowest level since May 2010.
Following the meeting in Vienna, Opec’s secretary general Abdallah Salem el-Badri said the group would not try to bolster prices by cutting output.
“There’s a price decline. That does not mean that we should really rush and do something,” he said.