Brent futures slipped below $112 per barrel on Wednesday as investors awaited Chinese trade data, US corporate earnings and the outcome of a European Central Bank policy meeting to glean insights into the health of the world's biggest economies.

China, the world's biggest energy consumer, will release its December trade figures on Thursday and fourth-quarter economic growth numbers on 18 January, while the ECB and Bank of England will begin their policy meetings later in the day.

Investor caution preceding the events also kept a lid on Asian stock gains. For the oil markets, inventory data showing a jump in US crude stockpiles added to the pressure.

Front-month Brent futures shed 17 cents to $111.77 per barrel early on Wednesday, after adding 54 cents on Tuesday. US crude was trading down 12 cents at $93.03 per barrel.

"What we're seeing in the oil markets is the cautious sentiment playing up ahead of some key economic events this week," said Ker Chung Yang, senior investment analyst at Phillips Futures Pte in Singapore.

"Trading at the start of the year is typically steady and I expect prices to remain range bound in the first quarter."

US crude futures slid while Brent rose in the previous session when the annual rebalancing of the S&P GSCI commodity index kicked in, prompting index funds to adjust their portfolios accordingly.

The rebalancing, announced in early November, will increase the index's holdings of Brent and reduce holdings of WTI as the output of Brent-related grades wanes and US crude output surges. The passive index rolls its holdings between the fifth and ninth trading days of the month.

US corporate profits are expected to be higher than the third quarter's lacklustre results, but analysts' estimates are down sharply from where they were in October.

"Oil markets are watching the US fourth-quarter earnings; from a general market point of view, a good start to the Q4 earnings season will set a bullish tone in the market," said Natalie Rampono, senior commodity strategist at ANZ.

The Ban of England and ECB policymakers will begin two-day meetings on Wednesday and investors will be looking for hints that the ECB may lower interest rates in 2013 to pull the regional economy out of recession.

China's data also remains in focus. Reuters polls predicted that the trade numbers may show marginal improvement in the economy, although weak US and European demand may weigh on exports. Economic growth may have accelerated, ending seven quarters of weaker expansion.

"Global economic growth is expected to ramp up this year... this should bode well for oil demand," Deutsche Bank analysts wrote in their outlook for the year released on Tuesday.

"We forecast oil prices will pick up in the 2H 2013 in line with accelerating economic growth."

The bank expects Brent to average $115 per barrel and US crude to average $100 per barrel in the second half of 2013.

Weighing on prices, the US Energy Information Administration said on Tuesday that the country's crude production would rise by the biggest margin on record in 2013, and is set to soar by a quarter over two years.

The rapid increase underscores how improvements in horizontal drilling and hydraulic fracturing technology have transformed the energy market in the last five years, allowing producers to tap shale oil from tight rock formations.

Adding to the pressure, the American Petroleum Institute (API) said crude stocks rose 2.4 million barrels last week, beating analysts' expectations of a 1.5 million barrel increase.

The increase was largely due to a 1.2 million barrel per day jump in crude imports, API said.