OPEC refrained from changing its oil output policy on Thursday, meaning the organization failed to agree on a new production ceiling, an OPEC delegate told Reuters.
Two delegates also said Nigerian candidate Mohammed Barkindo was chosen to be OPEC's new secretary-general.
The Organization of the Petroleum Exporting Countries last decided to change output in December 2008, and for oil-price hawks such as Iran, fears are growing that the 56-year-old OPEC is losing its role as a production-setting cartel and turning into a talking shop.
WTI futures sank on the news with oil trading at $48 a barrel, after starting the session around $49.0 a barrel.
Speaking after the meeting, Saudi Arabia's oil minister, Khalid Al-Falih told CNBC that the spirit of the meeting was very cooperative and collaborative.
"We are extremely happy, I think the market is in good shape. The market is balancing, trends are all good in terms of supply and demand. prices have recovered somewhat and I believe that they will continue to recover," he said.
Meanwhile, Iranian Oil Minister Bijan Zanganeh told CNBC that OPEC members did not discuss a production freeze.
"It seems that the members believe that it should manage the market without discussing about the freeze. Because a freeze, I think is a matter of history," he said.