SINGAPORE - Oil prices extended their decline Friday after the Organization of Petroleum Exporting Countries agreed not to change its output targets, as expected.

Traders at the New York Mercantile Exchange deal oil futures contracts, Tuesday, March 13, 2007. [AP]

Light, sweet crude for April delivery lost 19 cents to $57.36 a barrel in Asian electronic trading on the New York Mercantile Exchange as of midmorning in Singapore. The contract fell 61 cents to settle at $57.55 a barrel Thursday.

OPEC ministers said Thursday at a meeting in Vienna that they had decided to maintain the oil cartel's crude production at existing levels, satisfied that two recent rounds of output cutbacks have helped boost sagging oil prices and balance global oil markets.

"The market is stable, the market is healthy," said OPEC Secretary General Abdalla Salem El-Badri of Libya. "We don't need to touch it this time."

OPEC, though, also warned that oil price volatility is likely to continue in 2007. Prices have zigzagged recently, sometimes sharply during the same day, buoyed by tensions with Iran and weighed by mild winter temperatures in the Northeast. OPEC agreed to meet again on Sept. 11 to review market conditions.

The market had expected OPEC to keep the status quo. Still, production could fall if ministers implement compliance with cuts agreed on in the past four months.

In meetings late last year, OPEC agreed to take a combined 1.7 million barrels a day off global oil markets as they sought to shore up sagging oil prices and shrink burgeoning inventories. Actual cuts have been only about 1 million barrels a day.

Oil prices recently have also been reacting to the stock market, as dips in US equities spur fears of possible weaker demand.

Heating oil futures dropped 0.11 cent to $1.6874 a gallon, while natural gas prices declined by a cent to $6.949 per 1,000 cubic feet.