Oil futures settled lower on Friday as worries over excess supply on the back of strong output from some of the world’s major oil producers weighed on prices for a second straight session, but prices logged a gain for the week on signs of a slowdown in U.S. production.

July crude fell 81 cents, or 1.3%, to settle at $59.96 a barrel on the New York Mercantile Exchange. Based on the most-active contracts, prices saw a gain of around 1.4% on the week. July Brent crude on London’s ICE Futures exchange fell $1.24, or 1.9%, to $63.87 a barrel. The July contract, which expires on Monday, was up about 0.8% for the week, but tracking the most-active contracts, prices were up around 2.1% for the week.

“Traders were excited to see that the U.S. drilling activity has slowed down further, but this optimism was cooled” by the fact that members of the Organization of the Petroleum Exporting Countries are “pumping more oil and this is pulling the price of oil lower,” said Naeem Aslam, chief market analyst at Ava Trade. OPEC has been producing roughly 1 million barrels a day or more above its production ceiling of 30 million barrels a day, which it affirmed at a meeting last week. “This confirms that the organization is only interested in saving its market share—especially Saudi Arabia,” Aslam said.

Looking ahead, Daniel Ang, analyst at Phillip Futures, said next week’s crucial Federal Reserve policy meetingwill likely move the U.S. dollar Index which can influence trading of dollar-denominated oil. Ang expects Nymex and Brent oil futures to find support at $60 and $64 a barrel, respectively. Meanwhile, the International Energy Agency report published Thursday had something for both oil market bulls and bears, but ultimately the market tightening continues, said analyst Oswald Clint at Sanford S. Bernstein. The market appeared unfazed by data from Baker Hughes Friday showing that the number of U.S. rigs actively drilling for oil fell for a 27th week in a row. Active oil drilling rigs fell 7 to 635 as of June 12. Back on Nymex, July gasoline fell 1.7 cents, or 0.8%, to $2.121 a gallon, with prices up around 4.5% for the week, and July heating oil lost 3.2 cents, or 1.7%, to $1.889 a gallon, gaining about 1.1% for the week.