* Futures up: Dow 81 pts, S&P 9.5 pts, Nasdaq 23 pts
By Abhiram Nandakumar
March 9 (Reuters) - U.S. stock index futures were higher on Wednesday, tracking a rise in oil prices, even as investors remained wary of weakness in the global economy, led by China.
* Benchmark Brent rose above $40 a barrel in anticipation that the world's largest exporters would agree to freeze production and help reduce a massive oversupply.
* Crude prices, which have been a major influence on stocks this year, have rallied sharply in recent days. However, industry watchers remain skeptical of a sustained recovery due to the glut.
* Markets worldwide were lower on Wednesday as investors fretted about global economic conditions ahead of central bank meetings on monetary policies.
* While recent data has pointed to a recovery in the U.S. economy, reports out of Asia and the euro zone continue to paint a picture of faltering growth.
* The European Central Bank, which will meet later this week, is expected to increase its stimulus program.
* While the U.S. Federal Reserve is not expected to raise interest rates at its meeting on March 15-16, the central bank has said it is on track to raise rates gradually this year.
* U.S. stocks fell on Tuesday, snapping a five-day run of gains on the S&P 500 and the Dow Jones industrial average, after a slump in oil prices dragged down energy shares.
* Shares of Chipotle Mexican Grill were down 3.3 percent at $524.69 premarket. The company, already reeling from several food-borne illnesses, temporarily shut a Massachusetts restaurant after four employees fell sick.
* Ross Stores was down 1.4 percent at $57.38 after Goldman Sachs cut its rating on the stock to neutral.
Futures snapshot at 6:40 a.m. ET:
* Dow e-minis were up 81 points, or 0.48 percent, with 21,967 contracts changing hands.
* S&P 500 e-minis were up 9.5 points, or 0.48 percent, with 145,824 contracts traded.
* Nasdaq 100 e-minis were up 23 points, or 0.54 percent, on volume of 22,210 contracts. (Reporting by Abhiram Nandakumar in Bengaluru; Editing by Anil D'Silva)