On the New York Mercantile Exchange a barrel of benchmark "light sweet crude" for February delivery was down 51 cents from Thursday at $91.00. The market was closed on Friday.
China's decision to further hike interest rates in order to tame inflation raised the prospect of slower growth in the world's hottest emerging market.
"There are concerns about Chinese growth," said Jason Schenker of Prestige Economics.
However London's Brent North Sea crude for February delivery rose eight cents from Friday to $93.85 a barrel.
US traders predicted crude prices would resume their rise later in the week on the expectation of a surge in demand for heating fuel in the face of a huge snowstorm in the US northeast and record low temperatures in Europe.
Most of the US heating fuel supply is consumed in the northeast.
Oil prices last rose above $100 a barrel on October 2, 2008. Prices have firmed considerably in recent days in response to macroeconomic data suggesting that the recovery in the United States, the world's leading energy consumer, was gathering strength.
Prices have risen more than $11 in New York since the start of the year and more than $15 in London.
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