Oil prices fell sharply on Friday as traders remained dubious about the ability of the Organization of Petroleum Exporting Countries (OPEC) to implement its cut plan.

New York's main contract, light sweet crude for delivery in November, dived 1.68 dollars to close at 56.82 dollars a barrel, the lowest this year. In London, Brent North Sea crude for December delivery fell 1.19 dollars to settle at 59.68 dollars a barrel.

OPEC announced Friday a deal to cut the cartel's oil output by 1.2 million barrels per day from Nov. 1.

The decision was made at OPEC's extraordinary meeting in Doha. It was the first time that OPEC curbed production since April 2004.

The cuts would come from actual production levels, said OPEC Vice Chairman and Oil Minister of the United Arab Emirates Mohammed bin Dhain al-Hamili after the meeting.

The output cut was aimed at boosting prices, which have declined more than 25 percent since mid-July.

The U.S. Energy Department reported Wednesday that the nation's commercial crude oil reserves rose by 5.1 million barrels to 335.6 million.

Source: Xinhua