Canadian producers are struggling to cut the cost of extracting bitumen from the oil sands, and their other wells are failing to match the efficiency gains of U.S. rivals, a Bloomberg Intelligence analysis shows. While output keeps rising in the Permian Basin, the largest U.S. shale play, companies are slowing output from wells in Alberta and have shelved 18 oil- sands projects during the downturn, according to ARC Financial Corp.

OPEC’s board of governors was unable to agree on the group’s long-term strategy plan and won’t present it to oil ministers when they meet on Dec. 4 in Vienna, two OPEC delegates with knowledge of the matter said.

“The drop in prices won’t be a concern for us,” Zanganeh said. “It should be a concern for those who have replaced Iran.” Iran doesn’t expect difficulties selling the additional barrels, and “the market has taken into account our return,” he said.

OPEC’s share of the global oil market will expand from 2020 as prices recover to $80 and supply outside the group stagnates due to spending cuts, according to the International Energy Agency.

Internal OPEC squabbles are on the rise as members argue about the need to support a fair oil price and boost revenues just as they feel more pain from low crude prices.

The plan appears to be working. Oil remains 33 percent lower than when OPEC revealed its strategy on Nov. 27, trading for $48.38 a barrel at 10:13 a.m. in London Wednesday. U.S. crude production has retreated about 500,000 barrels a day from the three-decade peak reached in June to 9.1 million a day in the week to Oct. 9, according to data from the Energy Information Administration.

Russia, Kazakhstan and Azerbaijan all have safety cushions of income from oil and gas to help in the hard times of benchmark Brent crude under $50 a barrel.

Saudi Arabia's crude oil exports fell by 278,000 barrels per day in August, despite historically high wellhead production, while volumes of shipped refined oil products rose to a record high, official data showed on Sunday.

World economic growth has been revised down to 3.1% for 2015 and to 3.4% for 2016. While OECD growth remains unchanged at 2.0% for 2015 and 2.1% in 2016, major emerging economies are increasingly facing challenges. China’s and India’s growth forecasts have been revised down by 0.1 percentage points to now stand at 6.8% and 6.4% for China and at 7.4% and 7.6% for India in 2015 and 2016, respectively.

The oil price collapse over the past 16 months has forced the world’s biggest energy companies to cut hundreds of billions of dollars in future spending to bolster their balance sheets. But Ali al-Naimi — oil minister and architect of the Saudi strategy to maintain output and keep prices low to hobble its rivals — voiced a commitment to press on with investments in exploration, production and refining.