World oil prices fell on Monday as figures showing that China's manufacturing activity contracting for the second month running in September added to concerns about weak energy demand, analysts said.
Brent North Sea crude for delivery in November retreated 32 cents to $112.07 a barrel in London midday trading.
New York's main contract, light sweet crude for November, shed 18 cents to $92.01 a barrel.
"Crude oil prices started the week on the negative side as investors' sentiment has been hurt following persistent concerns about a global economic slowdown and a lack of oil demand at the last quarter of 2012," said Sucden Financial Research analyst Myrto Sokou.
Official data released by China showed manufacturing activity in the world's biggest energy consumer shrinking yet again.
China's manufacturing purchasing managers' index (PMI) was at 49.8 in September, up 0.6 from the August level but still below 50, indicating a contraction.
British bank HSBC had on Saturday published its own PMI figure of 47.9, its 11th consecutive month of contraction.
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