The OPEC oil cartel led by Saudi Arabia and allied producers including Russia made another big swipe at propping up lagging crude prices Nov. 30, expanding some output cuts into next year.

Crude rallied as lower OPEC production and signs of shrinking U.S. oil inventories bolstered expectations for an end to the global surplus.

Oil climbed Oct. 13 as dwindling U.S. crude stockpiles and near-record Chinese imports signaled the worldwide glut is eroding.

Oil advanced to the highest level since May after U.S. gasoline stockpiles plunged to a 22-month low and exports of crude and fuels surged.

Oil topped $50 a barrel for the first time and closed at a six-week high amid heightened optimism that a demand resurgence is in the offing.

Oil slipped after an industry report was said to show a smaller-than-anticipated U.S. crude inventory decline.

Oil traded at its lowest in more than a week in New York on signs U.S. production is continuing to recover, undermining OPEC’s efforts to clear a global glut.

Oil eased losses as growth in U.S. drilling was partially offset by a weaker dollar.

The oil market is risking a supply crunch as producers cut spending on major projects to focus on short-term low-cost shale output in the United States, some of the top crude and products traders said.

Oil producers pledged to consider extending their pact limiting supply, as half a dozen nations said more time was needed to drain swollen stockpiles.