* Oil retreats after 8 pct gain Wednesday, biggest in two years
* Worries about global crude oversupply weigh heavily
* U.S. crude oil stocks rise 6.9 mln bbls -API
* Brent, U.S. crude both down more than 35 pct in 3 months (Adds industry data on U.S. crude inventories)
By Stephanie Kelly
NEW YORK, Dec 27 (Reuters) - Oil prices fell on Thursday, retreating from an 8 percent rally in the previous session as the oil market focused on signs of faltering global economic growth and record production of crude.
Brent crude LCOc1 futures dropped 4.24 percent, or $2.31, to settle at $52.16 a barrel. U.S. West Texas Intermediate (WTI) crude CLc1 futures fell $1.61 to settle at $44.61 a barrel, down 3.48 percent.
"The market is giving back some of its gains from yesterday that were brought along with the euphoria in the stock market," said Andrew Lipow, president of Lipow Oil Associates in Houston.
Prices surged on Wednesday, tracking a spike on Wall Street after President Donald Trump's administration attempted to shore up investor confidence. MKTS/GLOB
U.S. stocks retreated for most of the session on Thursday, dragging oil prices, before roaring back to end in positive territory. .N
Brent and WTI have lost more than a third of their value since the beginning of October and are heading for declines of more than 20 percent in 2018.
Concerns about slowing global economic growth have dampened investor demand for riskier asset classes and pressured crude futures.
Market participants are also worried about a glut of crude.
U.S. crude stocks rose by 6.9 million barrels in the week ended Dec. 21 to 448.2 million, data from industry group the American Petroleum Institute showed on Thursday. Analysts had expected a decrease of 2.9 million barrels. U.S. government data will be released on Friday.
Three months ago it looked as if the global oil market would be undersupplied through the northern hemisphere winter as U.S. sanctions removed large volumes of Iranian crude. But other oil exporters have compensated for any shortfall, depressing prices.
The Organization of the Petroleum Exporting Countries, along with Russia and other producers, agreed this month to reduce output by 1.2 million barrels per day (bpd), equivalent to more than 1 percent of global consumption.
But the cuts will not take effect until January and oil production has been at or near record highs in Russia, Saudi Arabia and the United States, now the world's top crude producer pumping 11.6 million bpd.
Russian Energy Minister Alexander Novak said the country will cut its output by between 3 million and 5 million tonnes in the first half of 2019. It then will be able to restore it to 556 million tonnes (11.12 million barrels per day) for the whole 2019, on par with 2018, he added. U.S. sanctions have put a cap on Iran's oil sales, Tehran has said its private exporters have "no problems" selling its oil.