He gave the warning in a statement as Schlumberger reported third-quarter earnings per share that were 48 per cent below the equivalent period of 2014, but slightly above analysts’ expectations.

The business environment deteriorated further in the third quarter. However, the cost reduction actions we took in previous quarters and the acceleration of our transformation program enabled us to protect our financial performance in what is shaping up to be the most severe downturn in the industry for decades. As a result of our actions, we have been able to deliver pretax operating margins well above those seen in any previous downturn and we have continued to generate significant liquidity with free cash flow of $1.7 billion in the third quarter, representing 170% of earnings.

Russia has for years been muscling in on Asian markets where Saudi Arabia was once the unchallenged dominant supplier. But now Riyadh is retaliating in Moscow's backyard of Europe with aggressive price discounting.

Brent crude was down 24 cents at $49.00 a barrel. Prices have more than halved from June 2014. U.S. crude fell 39 cents to $46.27 a barrel.

DEA Deutsche Erdoel (DEA), a company based in Germany controlled by Russian billionaire Mikhail Fridman’s investment firm LetterOne, signed an agreement to buy 100% of E.ON’s shares in E.ON E&P Norge for $1.6 billion, explaining that the transaction will allow DEA doubling its current production in Norway.

Spanish oil major Repsol said on Wednesday its net profit could fall by up to 22 percent in 2015, hit by low crude prices and a loss of value of some of its North-American assets which will trigger a big impairment charge in the third quarter.

“Today’s vote starts us down the path to a new era of energy security, saving consumers billions and creating jobs across the country,” said API President and CEO Jack Gerard. “American producers would be able to compete on a level playing field with countries like Iran and Russia, providing security to our allies and accelerating the energy revolution that has revitalized our economy.

"...in Europe investment signals are unclear. As a result of EU policy and lack of an expressed role of gas in these policies, there is an additional political risk concerning future European gas demand," Norway's Oil and Energy Ministry said in its reply to the European Commission, as a part of wider consultations on the EU's strategy on LNG and gas storage.

Nord Stream II would consist of two lines, doubling the 55-bcm annual capacity of the Nord Stream offshore pipeline which already runs from Vyborg near Russia's border with Finland to Greifswald in Germany.

Crude oil production in November from seven major US shale plays is expected to drop 93,000 b/d to 5.12 million b/d. That’s back up to the same level forecast for September after a somewhat smaller decline was projected for October.

"Considerable uncertainties" surrounded the U.S. economic outlook, particularly the drag on exports from slowing global growth, low investment caused by the decline in oil prices and a “disappointing” recent drop in U.S. job growth.

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.

Britain has told Russian oligarch Mikhail Fridman he was still welcome to invest in the country even after he was forced to divest gas assets there under pressure from the previous government.

Swiss chemicals giant Ineos has bought its first British North Sea gas fields from Russian billionaire Mikhail Fridman's investment fund LetterOne, outlining plans to further expand its energy resources to supports its petrochemical business.

Rosneft, as part of a PetroMiranda JV including PDVSA and Gazprom Neft, has drilled an unprecedented horizontal well GG1-14 at the Junin-6 block. The well is unique for the shallow depth, only 1,140 feet or about 347 meters, of the reservoir interval and the length of horizontal section 4,920 feet or 1,500 meters. The total length of the well is 6,059 feet (some 1,847 meters).