Saudi oil minister Ali Naimi called it "one of the worst meetings we've ever had," while analysts covering OPEC for more than 20 years said they could not remember any other time that the normally closed group had admitted to such divisions in its ranks.
Some even saw the abortive meeting as a harbinger of demise for the organization, which produces more than a third of the world's petroleum.
"OPEC is . . . on the point of breakup," said Marc Ostwald, of Monument Securities. "A broader perspective is that the post- World War II world order is fracturing in a spectacular fashion, be it the EU/Eurozone, the World Bank/IMF, [or] OPEC."
The news caught markets by surprise, sending oil prices sharply higher. Benchmark crude for July delivery was up $1.25 to $100.34 per barrel in morning trading on the New York Mercantile Exchange after trading lower ahead of the OPEC meeting.
Saudi Arabia had pushed to increase production ceilings to calm markets and ease concerns that crude was overpriced for consumer nations struggling with their economies. Those opposed were led by Iran, the second-strongest producer within the Organization of the Petroleum Exporting Countries.
The Saudis and the Iranians are frequently at loggerheads over pricing, but past meetings have usually fallen in behind Saudi Arabia, which produces the lion's share of OPEC output. But this time, the Saudi-Iranian rivalry, combined with major political and economic uncertainties, led to deadlock.
Among the biggest worries is that unrest in Libya and Yemen could destabilize larger oil-producing nations in the region. Saudi Arabia and others have boosted output to make up for much of the daily 1.6 million barrels normally brought to the market by Libya, other OPEC nations - already pumping close to capacity - cannot contribute much. This appeared to have fueled the strong opposition to an output ceiling hike.