London - Global oil prices fell further Thursday as dealers focused on an unexpectedly large surge in US crude stockpiles, stoking concerns about oversupply in the world's biggest economy.
New York's main contract, West Texas Intermediate (WTI) for delivery in January dipped 14 cents to $92.16 a barrel.
Brent North Sea crude for January declined 33 cents to stand at $110.98 a barrel in London midday trade.
Crude futures also sank on Wednesday after the US government's Department of Energy reported that commercial stocks of oil increased by three million barrels last week.
That was well above the 500 000 barrels forecast by analysts in a Wall Street Journal survey.
Wednesday's rise in crude stockpiles was the latest in a series of surprisingly large builds in recent weeks.
Since September 13, commercial crude stocks have increased 35.8 million, or more than 10 percent.
"WTI crude oil suffered significant losses over the last two days, mostly driven by stockpiles concerns in the US," Singapore-based brokers Phillip Futures said in a note.
"High US stockpiles are likely to be contributed by persistent strong production in the nation," it said, adding that output hit 8.02 million barrels in the week to November 22, the highest level since January 1989.
US oil prices traded above $100 a barrel for much of the summer, but have dipped below that since October 21 due to rising supplies and easing geopolitical tensions, including Washington's decision to hold off military action in Syria and better relations with Iran.
European benchmark Brent remained supported by escalating concerns over political strife in Libya, a member of the OPEC oil producing cartel, analysts said.
Protesters with a wide range of demands have been blocking oil and gas export terminals since late July, causing revenues to plunge 80 percent.