OPEC left its oil output target unchanged on Wednesday, a decision that sent crude prices shooting higher on global markets and exposed deep divisions in the cartel amid calls for a hike in quotas.

Traders had speculated that the Organization of Petroleum Exporting Countries would boost production to help cool high oil prices and in turn revive flagging economic growth.

"Unfortunately we are unable to reach a consensus this time to reduce or raise our production," OPEC Secretary General Abdullah El-Badri said after the meeting.

OPEC, which has a dozen member countries, kept its official output target at 24.84 million barrels per day (mbpd), where it has stood since January 2009.

However, the cartel is unofficially pumping above this level to compensate for OPEC member Libya, whose oil supplies have been ravaged by violent unrest since February. A Libyan representative also attended Wednesday's meeting.

Saudi Arabian Oil Minister Ali al-Naimi, speaking to reporters after the decision, said it was "one of the worst meetings we ever had."

"We were not able to reach an agreement," added Naimi, who confirmed that the Gulf nations of Saudi, Kuwait, Qatar and the United Arab Emirates had proposed an increase of 1.5 mbpd.

"That means we are suggesting production of 30.3 mbpd," he said, adding that Algeria, Angola, Venezuela, Iraq, Iran and Libya had rejected such a move.

OPEC kingpin Saudi Arabia is the world's biggest oil supplier and traditionally the most influential member of the cartel.

Following the latest decision, Brent oil prices shot up $1.62 to $118.40 a barrel in London trade and New York's light sweet crude climbed $1.75 to $100.84.

The International Energy Agency said it was "disappointed" by OPEC's decision and urged producers to pump more anyway to avoid higher oil prices.

"We have noted with disappointment that OPEC members today were unable to agree on the need to make more oil available to the market," said the Paris-based IEA, which represents the interests of industrialised nations.

Understanding that the output from the cartel does not always match the formally agreed quotas, the IEA added: "Of course what really matters is actual supply."

The IEA urged "key producers to respond accordingly" and pump more oil into the market to meet rising seasonal demand.

"Otherwise, a further tightening in the market and potential increases in prices risk undermining economic recovery, which is in the interests neither of producers or consumers," the IEA said.

Meanwhile, Iran's caretaker oil minister Mohammad Aliabadi -- whose country holds the rotating OPEC presidency -- acknowledged that there remained "much uncertainty about the strength of the world economic recovery."

El-Badri told reporters that OPEC had spare capacity of between 4.0-4.5 mbpd. That compared with 6.0-6.5 mbpd before the Libyan unrest erupted in February.

"There is enough supply in the market, there is no shortage whatsoever, even in the absence of one country, but ... we are not in crisis at at this time," said El-Badri, referring to the troubles in Libya.

"The reason that we are unable to reach a decision is that everyone has its own data .. some of them (the member nations) have different numbers."

The next meeting will be in mid-December in Vienna to reassess the oil market situation, he added.

"At the end of that period, we can make the appropriate decision but this decision (to maintain output quotas) was unfortunately not welcomed by certain members," El-Badri said.

Some OPEC members are worried that the oil market will tighten in the coming months -- as seasonal demand hits a peak in the northern hemisphere summer -- pushing oil prices even higher.