Oil steadied on Friday after sliding below $58 as Nigerian crude production increased, adding to pressure from ample US fuel stocks and doubt over Opec's resolve for supply curbs. US light crude for December delivery was down 2 cents at $57.86 a barrel, after falling 83 cents on Thursday to take losses for the week to nearly 5 percent.
London Brent crude traded flats at $57.87 a barrel. Royal Dutch Shell said on Thursday it resumed production of about 47,000 barrels per day at two of its flow stations in Nigeria. One flow station remained shut after attacks, while Chevron reopened its facility this week. The extra supplies helped traders shrug off larger-than-expected falls in US fuel inventories last week, given stocks are still above last year's levels heading into peak winter demand.
"Without cold weather, energy demand is likely to be lower and so crude oil, and later refined product, inventories are likely to remain comfortable," said Tobin Gorey of the Commonwealth Bank of Australia.
Traders are still waiting to see if Opec producers will adhere to an agreement to cut supplies by 1.2 million barrels per day from November. Consultancy Oil Movements sees Opec exports down by only 440,000 bpd in the four weeks to November 18. "The market remains sceptical that any more than half of the pledged cut will occur, leaving room for the market to be surprised either way," said Gorey.
Saudi Arabia and the United Arab Emirates have told their customers to expect less crude this month, but most other producers have yet to commit.
Trade sources said on Thursday Algeria had cut November oil supply in line with its pledge. Despite the Opec cutbacks oil prices are down 26 percent from a record high in mid-July after an investor sell-off.
Supply from non-Opec producer Russia also fell for the second month in a row in October to 9.71 million bpd, government data showed on Thursday. Data from the US Labour Department showed business productivity delivered no growth in the third quarter, leaving concerns that economic weakness could translate into slower energy demand.
However, world growth has withstood the impact of rising oil prices because firms and consumers have shared the burden of higher energy costs, the OED's chief economist said in an interview published on Thursday.