Brent North Sea crude for delivery in February shed 17 cents to $93.96 a barrel in afternoon London trade.
New York's main contract, light sweet crude for February slid 37 cents to $90.75 a barrel.
The US Department of Energy is to publish its latest weekly snapshot of oil stockpiles on Thursday, which comes amid a pick-up in demand for heating fuel as cold temperatures batter the northeast of the United States.
"Distillates are expected to have declined ... partly due to the cold weather," said Brenda Sullivan, an analyst at Sucden brokerage.
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