Oil markets ended the week lower, pressured by expectations of rising supply and an unexpected build in US crude inventories signaling a demand slowdown.
The international benchmark Brent crude traded at $66.44 per barrel at 2.53 p.m. local time (1153 GMT) on Friday, down around 1.4% from last week's close of $67.37.
Similarly, the American benchmark West Texas Intermediate (WTI) stood at $62.71 per barrel, down roughly 1.6% from $63.73 last Friday.
Prices had started the week on firmer ground, gaining on Monday and Tuesday as escalating clashes between Russia and Ukraine stoked supply concerns and expectations grew for a Federal Reserve interest rate cut in September.
The rally faltered midweek as concerns over US fuel demand clouded the outlook in the world's largest oil consumer.
Adding to the bearish sentiment, the US Energy Information Administration (EIA) reported that commercial crude inventories rose by 2.4 million barrels last week to 420.7 million barrels. Analysts had expected a draw of around 2 million barrels.
On Thursday, prices slid further after reports that the Organization of the Petroleum Exporting Countries and its allies (OPEC+) may agree to raise output at their meeting on Sunday.
Market attention is now focused on the OPEC+ meeting, where members are widely expected to discuss increasing production in October.
Analysts say the move would aim to reclaim market share lost in recent years to US shale producers.
The alliance had already agreed to raise supply by 547,000 barrels per day in September compared with August.
By Ebru Sengul Cevrioglu
Anadolu Agency
energy@aa.com.tr