New York's main contract, West Texas Intermediate for January delivery, was up 19 cents at $97.41 in mid-morning trade while Brent North Sea crude for February gained 12 cents to $108.56.

"The forecast that US crude stockpiles may have dipped about three million barrels last week is providing support to prices," Kenny Kan, market analyst at CMC Markets in Singapore, told AFP.

Analysts on average expect crude inventories declined 2.7 million barrels for the week ended December 13, according to a survey by Dow Jones Newswires.

The US Department of Energy will release the official petroleum inventory report later Wednesday.

The forecasted decline will follow a 10.6 million drawdown in inventories in the week to December 6, the second consecutive drop after a 10-week run of rises that had added more than 35 million barrels to supplies.

Kan said investors are also keenly awaiting the US Federal Reserve's decision on whether it will begin to scale back its $85 billion-a-month stimulus programme.

Fed policymakers will Wednesday wrap up a two-day meeting after debating whether economic conditions are strong enough wind down the scheme, which has been credited with helping to prop up global equity markets.

Any tapering would likely send the greenback higher, in turn making dollar-priced oil more expensive to people using other currencies.