Originally planned for November, the meeting was brought forward due to growing concerns about the impact of the financial crisis on the oil market.
Oil prices have fallen to a 16-month low amid fears a global economic recession will cut demand.
Thursday saw a mild market recovery as hopes rose that OPEC would cut output.
US light crude rose by more than $1.60 to nearly $70 a barrel, having earlier dropped to $66.20 a barrel - its lowest level since June 2007.
Oil prices hit an all-time high of $147 a barrel in July, but have since fallen back steadily.
A number of the cartel's 12 members say output should be reduced to stop the fall in prices: Venezuela wants production to be cut by a million barrels a day - 3% of Opec's total output. Iran has called for a cut twice that size.
The two countries are thought to be most in need of a relatively high oil price - around $100 a barrel - to finance government spending, says the BBC's economics correspondent, Andrew Walker.
Ali al-Naimi said oil prices would be determined by the market
Iran relies almost entirely on its oil exports for government revenue: for every dollar off the price of a barrel of oil, the country loses roughly $1bn a year in revenue.
But on Thursday, Saudi Oil Minister Ali al-Naimi would not be drawn on the subject of a possible output reduction, saying the price of oil would be determined by the market.
Opec's biggest oil producer, Saudi Arabia may be wary of aggravating economic problems in oil importing countries, our correspondent adds. Nor does it want to see high prices that might encourage users to switch away from oil to alternative energy sources.
Opec president Chakib Khelil said: "The decision should not leave the producer countries in the situation where they will be joining the group of countries which are already suffering from the financial crisis."
The cartel is reluctant to let the price drop below $70 a barrel.
Author: Jo Amey
