The U.S. government's Energy Information Administration (EIA) will issue its next weekly dataset for oil-supply demand on Wednesday.
While crude has rebounded this month, prices have struggled to hold above $50 a barrel this year as rising USA output stifles supply curbs by the Organization of Petroleum Exporting Countries.
Economists at the Organization of Petroleum Exporting Countries said in their monthly market report for September that total commercial oil stocks for members of the Organization for Economic Cooperation and Development were 195 million barrels above the five-year average and 123 million barrels above the seasonal norm.
The U.S. West Texas Intermediate crude October contract was at $50.51 a barrel by 07:15 a.m. ET (11:15 GMT), up 54 cents or about 1.08%, just off a four-month peak of $50.81 reached on Tuesday.
Benign inventory growth seen for US crude stocks last week - despite larger builds feared initially from refinery closures related to Hurricane Harvey - also underpinned prices. Georgi Slavov, head of research at commodities brokerage Marex Spectron said he does not expect demand for crude oil to rise significantly in the final quarter of this year, which means supply would have to be restricted even more tightly.
U.S. citizen fighting for Islamic State surrenders in Syria
On Thursday, the chief spokesman for the United States military command referred all questions about the news. The unnamed man is not the first American seized for participating in combat for ISIS.
Inventories of diesel and other distillates slid to the lowest level since 2011 while exporters shipped 5.42 million barrels of oil and fuels amid the recovery from Hurricane Harvey, the report showed. That is above the forecast for a rise of 2.4 million barrels by analysts surveyed by S&P Global Platts. The S&P Global Platts survey forecasts a fall of 800,000 barrels for gasoline and a 1 million-barrel draw for distillates.
"There are still a ton of barrels offshore looking to come onshore", he said, referring to stalled imports into the U.S. Gulf of Mexico since the hurricane.
Ministers from OPEC and its allies look set to keep everyone waiting longer for confirmation of further action to rebalance the oil market, sending conflicting signals on whether they'll discuss extending or deepening supply cuts in Vienna on Friday.
"Exempt members Libya and Nigeria may be bought into the fold of the production cut deal". The deal was extended in May through March 2018, but has been hindered by both a lack of compliance by some signatories and steady USA shale output.
Elsewhere, gasoline futures gained slipped 0.18% to $1.662 a gallon, while natural gas futures fwere steady at $3.123 per million British thermal units.