Crude oil futures eked out a small gain Tuesday ahead of a pivotal OPEC meeting in Vienna.

The cartel is expected to discuss whether to put a floor under prices by curtailing production.

January oil gained 20 cents, or 0.5%, to settle at $41.85/bbl on Nymex.

Demand concerns prevented a larger advance, as the Institute for Supply Management showed an unexpected contraction in U.S. manufacturing activity.

The ISM said its purchasing managers index dropped to 48.6 in November from 50.1 in October, with a reading below 50 indicating a contraction in manufacturing activity.

The material has been provided by InstaForex Company – www.instaforex.com