By Christopher Alessi

Brent crude fell below the $80-a-barrel threshold for the first time in nearly a month on Thursday, after data showed an unexpected rise in U.S. inventories.

Light, sweet crude for November delivery was 0.9% lower at $69.11 a barrel on the New York Mercantile Exchange. Brent crude, the global benchmark, was 1.1% lower at $79.19 a barrel.

The U.S. Energy Information Administration on Wednesday reported crude oil stockpiles had risen by 6.5 million barrels last week, to stand at 416.4 million barrels.

Earlier in October, Brent temporarily breached the $85-a-barrel level for the first time in roughly four years.

But prices have come under pressure over the past week, amid global stock market turmoil and signs of weakening oil demand. Both the International Energy Agency and OPEC last week lowered their oil demand growth forecasts for this year and next, in part due to a gloomier macroeconomic outlook.

"Stocks are rising in the U.S. and the reason is because pipes out of the U.S. for exports are maxed out while U.S. production is rising," said Bjarne Schieldrop, chief commodities analyst at SEB Markets.

The stock buildup also caused WTI to close down 3% Wednesday, while Brent ended the session down 1.7%.

Analysts at consultancy JBC Energy wrote in a daily note on Thursday that the "strong build in U.S. crude stocks was the fourth in a row, meaning that crude stocks have now built by over 22 million barrels in the past four weeks."

Oil prices had been boosted over the past month as a result of declining Iranian oil production ahead of the reimposition of sanctions on the Islamic Republic's oil industry at the start of next month.

The IEA last week said Iranian supply fell to a 2 1/2-year low in September as buyers continued to reduce their purchases before the Nov. 4 deadline. Crude production fell by 180,000 barrels a day month-on-month, to stand at 3.45 million barrels a day last month, the agency said.

Prices were also bolstered by a late September decision by the Organization of the Petroleum Exporting Countries and its partner producers not to ramp up crude output at a faster pace than planned. Saudi Arabia and Russia in June engineered a plan for OPEC and its allies to gradually begin increasing production after more than a year of holding back output.

Among refined products, gasoline futures for November delivery dropped 1.2% to $1.895 a gallon. Diesel futures fell 0.4%, to $2.3017 a gallon.

--Dan Molinski contributed to this article.

Write to Christopher Alessi at christopher.alessi@wsj.com

(END) Dow Jones Newswires

October 18, 2018 11:01 ET (15:01 GMT)

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