The 11-member Organization of Petroleum Exporting Countries, in an extraordinary meeting in Qatar's capital Doha, was seeking to reverse heavy falls in crude prices in an over-supplied market.

Opec officials had been talking of a one million bpd reduction but the meeting went further in the face of recent sustained price weakness.

New York's main contract, light sweet crude for November delivery, was up 40 cents at 58.90 dollars a barrel from 58.50 dollars in late US trades Thursday just ahead of Opec 's decision.

Brent North Sea crude for December climbed 33 cents to 61.20 dollars.

Victor Shum, senior principal with US energy consultancy Purvin and Gertz Inc in Singapore, said the market was reacting to Opec 's decision.

He said the cartel "has given what the market has been waiting for -- concrete evidence of Opec 's coordinated action to tighten up supply to stabilise prices."

Opec, which produces slightly more than a third of the world's oil, said it would cut current production by 1.2 million bpd to 26.3 million bpd from November 1.

Current output of 27.5 million bpd is below Opec 's official quota of 28 million bpd, which remains in place.

There had been some uncertainty over whether Opec would reduce output from the quota or current output levels, with the latter course having a more immediate impact.

"Heads of delegation noted with concern ... that crude oil supplies are well in excess of actual demand, as the above-average level of crude stocks in Oecd countries demonstrates, and that the oversupply situation and imbalance in supply-demand fundamentals have destabilised the market," an Opec statement said, referring to the Oecd zone covering most of the world's biggest economies.

Opec members had suggested ahead of the meeting that they would reduce production by one million bpd in a bid to shore up crude prices which have fallen more than 25 percent from record highs above 78 dollars in July.

In recent days the contract had traded below 58 dollars a barrel.

Analysts had expected that a cut in actual production would likely send oil prices higher, while a cut to the official quota would have seen them fall in a reflection of a lack of Opec determination and credibility.

Analysts said the market will watch closely to see whether the cartel members stick together on the cuts and how efficiently the move is implemented.

"They may decide to make cuts again in December," Shum said.

Tobin Gorey, a commodity analyst with Commonwealth Bank of Australia, said the market will be watching whether Opec carries through with the planned production cuts.

"We know they promised to cut," said Sydney-based Gorey. But the question now is, "will they stick to the cuts as well," he said.

"If they want to be seen as pretty sensible, they will have to act on what they have said."

The cartel's next regular meeting is set for Abuja, Nigeria, on December 14.

Several Opec ministers said ahead of the Doha talks that they were ready to support another cut if deemed necessary.

Japan expressed concern at Opec 's decision to cut oil production.

"If the aim was to maintain high oil prices, it is an extremely concerning situation," said Minister of Economy, Trade and Industry Akira Amari.

"We want the oil producers to provide supplies that meet global demand and to discuss ways to contribute to the stability of oil markets," he told a regular press conference.

Japan has to import all its oil, mostly from the Middle East, although Amari said the effect of the output cut would be cushioned by the higher yen, which makes dollar-priced oil relatively cheaper.

"The market has largely factored in the decision but the impact on Japan will not be zero," he said.