World oil prices were narrowly mixed on Wednesday as investors sat tight ahead of US energy inventory data.
New York's main contract, West Texas Intermediate crude for delivery in February, fell 38 cents to $101.86 a barrel.
Brent North Sea crude for February gained 11 cents to $113.39 in London midday deals.
The US Department of Energy on Wednesday updates the market on the health of energy inventories in the United States -- the world's biggest consumer of oil.
Analysts expect US crude stockpiles to have risen by 2.2 million barrels last week, according to Dow Jones Newswires.
Forecasters are also pricing in a jump in distillates -- which include heating fuel -- and gasoline (petrol).
Ahead of the data, traders continued to track events in Iran amid fears that the Islamic republic could decide to halt its oil exports to the West.
Iran has threatened to close the strategic Strait of Hormuz should the West go ahead with plans to slap a ban on imports of Iranian oil as part of sanctions to stop the country's disputed nuclear programme.
Hormuz links the Gulf with the Gulf of Oman -- through which much of the region's oil is transported.