But Saudi Oil Minister Ali al-Naimi said it was too early to judge whether or not Opec needed a second output reduction in three months to support oil prices.

"We know that stocks are building up and we are checking that and in Vienna we will discuss measures to make sure a drawdown takes place," Attiyah told reporters after a regular meeting of Gulf Cooperation Council (GCC) oil ministers.

Four of six GCC members Saudi, Kuwait, the United Arab Emirates and Qatar are also in the organization of the Petroleum Exporting Countries.

"There is no shortage of oil in the market, we have confirmed it, we have asked all of our customers," Attiyah, also Qatari oil minister, said.

Naimi, Opec's most influential minister, said producers would wait until the December 4 meeting to see if supply, demand and inventory data warranted another change in policy.

"I believe we should wait and look at the data when we meet on December 4 and decide accordingly. It is premature," he said.

Asked whether a September round of supply cuts was enough to prevent a stockbuild or whether more cuts were needed, Naimi said: "We will see that when inventories are examined at the end of the year. We do not know now."

Normally world crude oil stocks are drawn down in the fourth and first quarters, during the northern hemisphere winter, building again in the second and third quarters.

OPEC agreed a surprise production cut in September that sent oil prices rocketing to a peak last month of $32.50 a barrel for benchmark US crude.

Prices have since subsided, closing at $29.11 for US crude on Friday, but remain too high for comfort among industrialised economies seeking to foster economic growth.

The September deal, struck at a time when prices were close to $25 a barrel for OPEC's index of crudes, raised suspicion among some traders that the cartel might be aiming to keep prices near the top of its $22-$28 target range for the index.