West Texas Intermediate futures for October delivery, which expires today, fell to $46.30 (-1.41%), while Brent crude declined to $48.41 (-1.04%) as traders took profits after yesterday's gains.
Reuters reported on Tuesday based on official data that China's implied oil demand rose by 1.2% in August compared to July.
Some analysts say that prices have reached their bottom. However several banks including Goldman Sachs and ANZ cut their price forecasts this month, arguing it will take until next year or 2017 to reduce supply glut.