U.S. futures on Friday looked to add to weekly losses, pushing the commodity toward a 10th straight fall and into bear-market territory, as output increases fueled concerns of surging supplies.

On Thursday, U.S. crude benchmark’s descended into a bear market, usually defined as a drop of at least 20% from a recent peak, ending its longest bull market since early 2015.

In Friday dealings, West Texas Intermediate crude for December delivery CLZ8, -0.64%  was down 73 cents, or 1.2%, at $59.94 a barrel on the New York Mercantile Exchange, poised for the lowest front-month contract settlement since mid-February, according to FactSet data.

Read: The oil rout just became a bear market for U.S. crude

January Brent crude LCOF9, -0.59%  also fell 88 cents, or 1.3%, to reach $69.78 a barrel on ICE Futures Europe. Brent oil was down more than 19% from its recent October peak and flirting with a bear market. A settlement of $69.032 would mark Brent’s entry into a bear market.

For the week, WTI was set to drop 5.1%, while Brent crude was poised for a 4.1% decline, according to FactSet data.

The front-month WTI contract has so far posted declines in each of the last nine sessions. If it ends lower on Friday, that will mark the 10th consecutive decline and match the longest skid for the contract since a similar stretch from July 18, 1984 to July 31, 1984, according to Dow Jones Market Data.

“The declines we’ve seen over the last several days has been a reflection on the supply builds we’ve seen domestically in the last several weeks,” Matt Cook, associate editorial director for the Americas crude and fuel oil market at S&P Global Platts, told MarketWatch. “We’ve seen U.S. crude inventories build for the past seven weeks.”

“Market structure flipped into contango back in mid-October, which implies that the market is well-supplied for the moment,” Cook added. In contango, prices for future delivery rise above the spot market, which can encourage traders to store oil.

Looking ahead, investors will be awaiting data at 1 p.m. Eastern Time from Baker Hughes BHGE, +0.41% as a measure of the outlook for crude production. Last week, the number of active U.S. rigs drilling for oil edged down by 1 to 874 rigs, after rising for three weeks in a row.

Overall, crude output in Saudi Arabia, Russia and the U.S. had climbed ahead of U.S. sanctions on the Iranian energy sector, which were expected to contribute to tighter global oil supplies. The sanctions began earlier this week, but the U.S. granted eight countries temporary waivers—allowing them to continue buying Iranian oil.

The Energy Information Administration on Wednesday reported that U.S. production climbed by 400,000 barrels a day to a record 11.6 million barrels a day for the week ended Nov. 2.

A committee comprised of members of the Organization of the Petroleum Exporting Countries and some of its oil-producer allies will meet in Abu Dhabi over the weekend ahead of a key meeting on Dec. 6 in Vienna.

S&P Global Platts reported Thursday that the Joint OPEC-Non-OPEC Ministerial Monitoring Committee, which monitor implementation of crude output agreement that began on Jan. 1, 2017 between members and nonmembers, may recommend a 1 million barrel-per-day production cut to make up for the production boost from Russia and Saudi Arabia.

Meanwhile, Saudi Aramco CEO, Amin Nasser, is scheduled to meet in Moscow Friday with his counterpart at Rosneft, Igor Sechin, among other top oil executives.

Iran sanctions had previously served to boost oil prices, with an October swoon serving as a reflection that increased output by Saudi Arabia and Russia would largely offset the lost barrels. The U.S. announcement of waivers only added to worries about oversupply.

“OPEC has been increasing production since the June OPEC meeting in an effort to make up for lost Iran barrels. Problem is, Iran barrels did not disappear under the Trump plan, despite all the bark about zero exports,” wrote Robert Yawger, director of energy at Mizuho USA, in a Friday report.

“So…OPEC production is super-sized, Iran barrels are still flowing. And EIA storage packs seven storage builds on top of an already oversupplied market! That is how you slide to correction territory in one month!” He wrote.

Saudi Arabia’s production rose to 10.67 million barrels a day in October, according to an S&P Global Platts survey Wednesday. That was the most in the 30-year history of the survey.

Russia’s crude production rose to a post-Soviet record of 11.4 million barrels a day in October, according to Bloomberg.

On top of all of that, The Wall Street Journal, citing people familiar with the matter, wrote on Thursday that Saudi Arabia’s top government-funded think tank is studying the possible effects on oil markets of a breakup of OPEC.

Read: Saudi Arabia ponders a future without OPEC

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