Oil prices fell after the world’s biggest oil producer, Shell, cut its outlook on the future of the industry.
But oil prices have rallied in the past week, buoyed by an OPEC decision to cut production by 4 million barrels per day (bpd) for the first time in years.
Shell shares were down 2.4% to $30.70.
Oil prices have climbed in the first six months of this year as the global oil glut has been broken.
The global crude market is expected to hit $100 billion by 2020, and the Organization of the Petroleum Exporting Countries said on Wednesday it would boost production by 5 million bpd.
Shell has said that it wants to avoid a sharp decline in oil prices in order to focus on producing and marketing its Arctic oil.
In an after-hour trade session, Shell shares dropped 2.5% to their lowest level since May, and fell another 1.8% in after hours trading.
Shares in U.S. oil producer Phillips 66 were also down 2%.
The shares are down about 20% from a record high on Friday, according to Bloomberg data.
The benchmark S&P 500 index fell 0.4%.
Oil prices are down over 80% from their peak in mid-2014.
The drop in prices comes as U.N. Secretary-General Antonio Guterres said on Thursday that world production was at its lowest level in three years, despite an increase in oil demand from China and other countries.
Guterre said that despite the slowdown in the global economy, he hoped that oil prices would recover soon.
“The price of oil has been declining for more than a decade and there is still no sign of a major decline in world demand,” Guterrez said in a statement.
“It is a reality that we must now face, but that is not to say that it will not come.”
Shell shares fell 2.6% to close at $35.75.
The company’s shares were last down 3% at $40.70 in early afternoon trading.