Oil prices fell for a third day straight on Wednesday on growing expectations that supply growth will outpace demand growth next year.
Both benchmarks posted gains of about 8% last week.
Oil prices eased on Wednesday, taking a breather after gains earlier this week.
Oil prices rose by more than $1 a barrel on Monday after top exporter Saudi Arabia raised prices for its crude sold to Asia and the United States.
The situation with oil prices has not demonstrated stability over the past 4 months.
Over the past week, world oil quotations have experienced serious volatility.