Oil prices fell on expectations for weaker demand after two closely watched surveys underscored enduring global economic weakness.
Benchmark oil for November delivery was down 12 cents to $92.07 per barrel at midday Bangkok time in electronic trading on the New York Mercantile Exchange. The contract rose 34 cents to finish at $92.19 per barrel on the Nymex on Friday.
Brent crude was down 21 cents to $112.18 on the ICE Futures exchange in London.
Japan's central bank on Monday released a survey that shows deepening pessimism over the economy among the country's big manufacturers.
The Bank of Japan's quarterly "tankan" index was minus 3, a worsening from the previous quarter's minus 1.
Meanwhile, a survey by the China Federation of Logistics & Purchasing said its monthly index of manufacturing activity stood at 49.8 points on a 100-point scale. Numbers below 50 indicate a contraction. China's economic growth fell to a three-year low of 7.6 percent in the quarter ending in June.
Traders are now looking to upcoming jobs data out of the U.S. for a read on the health of the world's No. 1 economy.
"With Wednesday's presidential debates and the approaching election, we expect all eyes will be on Friday's non-farm payrolls data," said oil analyst Stephen Schork in an email commentary.