Oil prices rose on Aug. 31, boosted by a large drawdown in U.S. crude inventories and production cuts by OPEC+, but a slowdown in China's manufacturing activity limited gains.

Brent crude futures for October, expiring on Aug. 31, rose 45 cents, or 0.5%, to $86.31/bbl by 1004 GMT. The more active November contract was up 25 cents, or 0.3%, at $85.49.

U.S. West Texas Intermediate crude futures for October rose 29 cents, or 0.4%, to $81.29.

U.S. government data on Aug. 30 showed the country's crude inventories fell by a larger than expected 10.6 MMbbl last week, depleted by high exports and refinery runs.

Meanwhile, analysts expect Saudi Arabia to extend a voluntary oil production cut of 1 MMbbl/d into October, adding to cuts put in place by the Organization of the Petroleum Exporting Countries (OPEC) and allies led by Russia, a combination known as OPEC+.

"With Brent prices having stalled in the mid-$80s...the prospect of those Saudi barrels returning to the market any time soon looks slim and the impact is increasingly being felt across the world as commercial stock levels of crude and fuel products continue to drop," said Saxo Bank analyst Ole Hansen.

Weak Chinese factory data weighed on prices, however.

China's manufacturing activity shrank again in August, an official factory survey showed on Thursday, fueling concerns about weakness in the world's second-biggest economy.

The official purchasing managers' index (PMI) rose to 49.7 from 49.3 in July, the National Bureau of Statistics said, but it remained below the 50-point level. A reading above 50 points represents expansion from the previous month.

Investors are also awaiting inflation numbers as measured by U.S. personal consumption expenditures (PCE), which will be released on Aug. 31 and is the U.S. Federal Reserve's preferred gauge of inflation. Meanwhile, the U.S. government revised down its gross domestic product (GDP) growth to 2.1% in the past quarter, from the 2.4% pace reported last month, and data released on Wednesday showed private payroll growth slowed significantly in August.

The Fed can end its cycle of increases to interest rates if the labour market and economic growth continue to slow at the current gradual pace, the former president of the Boston Fed said on Aug. 30.