The Organization of Petroleum Exporting Countries (OPEC) has recently taken a series of measures to reduce the high price in the world oil market, but they have been proven to have little effect.

OPEC President Purnomo Yusgiantoro said Thursday that his organization will do its best to reduce the oil price to a level acceptable to both oil producing and consuming countries, including taking measures to ramp up its spare production capacity.

"OPEC is working to increase its (surplus) production capacities from 2.5 to 3.5 million barrels a day by the end of the year, depending on the call on OPEC oil," Yusgiantoro, also Indonesia's minister of energy and mineral resources, said at a news conference here.

However, the international oil price remains high this week, with the average price hiking to 36.89 US dollars a barrel on Monday. This is the highest since OPEC decided to raise daily output in July.

Against the background of rising world demand for oil, OPEC agreed in June to raise its official output ceiling by 2.5 million barrels per day (bpd) in two stages.

OPEC first increased production by 2 million bpd on July 1 and was set to raise output by a further 500,000 bpd from Aug. 1, making the total output amount to 26 million bpd within 10 OPEC members excluding Iraq.

OPEC seems to master the oil price very well in recent years through controlling production including the measures it took in March to raise the oil price. But this time, it doesn't work as efficiently as before.

Regarding prices exceeding the target range set by OPEC of 22 to 28 dollars per barrel, Yusgiantoro said the cartel would discuss its price band at a meeting in September.

"The price band is under study and it will be discussed in September by the (OPEC) ministers," he said.

Market analysts attributed OPEC's failure to affect oil prices to two factors.

The first is that the actual daily output within OPEC has already surpassed the ceiling, thus the means through adjusting ceiling to affect prices is out of date.In June, the output exceeded the ceiling by 10 percent.

Saudi Arabia, the world largest oil exporter has increased its output to 9.4 million bpd, surpassing its quota by 23 percent, said statistics.

Secondly, the output capacity of OPEC members have reached their peaks, which makes them reluctant to further raise production.

According to David Fyfe, an expert of the International Energy Agency, OPEC's second rise of official output ceiling is only "a target bpd," which is of "no significance" when the members do not abide by the ceiling already.

In addition, the policy introduced by OPEC also indicated that the oil prices will not drop by a big margin in the near future.

In order to make use of the weakness of the dollar to export more oil, OPEC turned a blind eye to its target price band between 22 and 28 dollars, which actually existed in name only since the beginning of this year.

Although reports say an expert committee is considering to raise the target price band, the earliest time for OPEC members to discuss the issue would be the end of this year.

If the supply in the world oil market could not meet the demand by the global economic development, the high prices will continue for a long time.

According to a report by the International Energy Agency issued in July, the average daily demand of crude oil in the world stands at 81.4 million bpd this year, 3.2 percent higher than that of last year.

In 2005, the daily demand could reach 83.2 million bpd, said the report.

Committed to doing everything to restore prices, Yusgiantoro admitted, "We in OPEC accept that this is a challenging time in the oil market."