NYMEX crude for April delivery was down 34 cents, or around 1%, at $34.06 a barrel, after settling up 65 cents on Tuesday on the back of firm Wall Street. US crude hit a one-month high on Tuesday.

US crude inventories rose by 9.9 million barrels last week, data from the American Petroleum Institute showed after Tuesday's settlement. That was well above a 3.6-million barrel increase expected by analysts in a Reuters poll.

Some traders were bracing for the possibility that official data from the Energy Information Administration (EIA) due later in the day would show a large build similar to the industry numbers, which could cut short the oil market rebound of the past two weeks.

Despite the losses, crude prices have trended higher in the last fortnight since hitting 12-year lows under $30 a barrel between late January and mid-February.

"Sentiment has clearly shifted for commodities in the last fortnight," ANZ bank said on Wednesday. "Both crude oil and iron ore prices hit a one-month high overnight. The price action in oil adds to the case that the bottom in the crude oil market is now in place."

Crude prices were supported by Russian Energy Minister Alexander Novak's remarks that oil companies in the country support a pledge to average production this year at January's levels but did not support any proposals to cut oil production.

Russian President Vladimir Putin spoke of "more radical" measures to balance the global oil market, on top of a production freeze plan jointly pursued by Moscow with Saudi Arabia, Qatar and Venezuela.