The continuing surge in oil prices is proving Opec's limited influence on the market despite the cartel committing to increasing its production ceiling, analysts said.
"Opec's role to shift prices is limited because of the weakness in its spare production capacity which, estimated at one to 1.5 million barrels per day (bpd), constitutes heavy crude" that is not sought after by refineries, analyst Waleed Khaduri told AFP.
However, the Organisation of Petroleum Exporting Countries remains a sizeable force in the world economy, to which it provides 30 to 80 million bpd of crude, said Khaduri, chief editor of the Middle East Economic Survey (MEES), based in Nicosia.
Crude oil futures jumped to a record high closing on the New York Mercantile Exchange on Friday, as markets fretted over tight US supplies despite a decision to release small amounts from a strategic reserve.
The November contract for light sweet crude climbed 42 cents to 48.88 dollars a barrel at the close. The latest price eclipsed the prior all-time record close on August 19 of 48.70 dollars and neared the intraday record of 49.40 dollars on August 20.
In London, the price of benchmark Brent North Sea crude oil for delivery in November gained 20 cents to close at 45.33 dollars a barrel a day after reaching a new intraday record of 45.75 dollars.
Opec declared in Vienna on September 15 it was lifting its official production ceiling by one million barrels daily to 27 million bpd from November 1.
But the decision left markets unmoved and has so far failed to bring down prices.
"Opec does not have the capacity to influence the oil market... which did not react to its decision to increase its production ceiling," said Kuwaiti analyst Kamal Abdullah al-Harmi.
"Opec is no longer able to impose a balance on the market, on which the cartel has lost its influence because it no longer has the spare production capacity" sufficient to do so, he added.
According to Harmi, the market needs light crude, produced notably by Libya, Algeria and Nigeria. Western refineries, notably American, don't want to use heavy crude which is produced by Gulf states and which constitutes Opec's spare capacity, he said.
The general view is that the quantity of oil in circulation is sufficient to immediately supply the market. But the spare capacity of producer countries, which is not providing a "security cushion" in the event of a disruption to production by any one of them, is at its lowest.
"Opec is not responsable for the rise in prices and is not able to lower" this upward trend, said Abdulwahab Abu Dahesh, who heads investment research at the Riyadh Bank in Saudi Arabia.
"According to expectations, Opec and non-Opec producer countries will need many years to increase their production capacity to a level which can reassure the market," said Abu Dahesh.
"Many producers did not invest in their oil sector during the 80s and 90s, marked by a fall in oil prices," he said.
Khaduri attributed the increase in prices to fears over future production capacity and geopolitical and climatic factors.
The Centre for Global Energy Studies warned last week that the course of oil prices is "largely out of the hands" of both Opec and the international energy industry, with markets set to remain tight over the coming months.