Brent crude LCOc1 had climbed 34 cents to $45.79 a barrel by 0650 GMT, while U.S. West Texas Intermediate crude futures CLc1 were up 36 cents at $43.52 a barrel, buoyed by a weaker dollar, according to report

Though rising in this session, Brent and WTI are on track for their biggest weekly losses since mid-January, hit by oil inventory builds and weak U.S. manufacturing data.

"Downward momentum is a feature of the oil market," said CMC Markets analyst Ric Spooner.

"The end of the U.S. driving season and the prospect of building inventories create downward risk for the oil price and may see further pressure on energy stocks today."

Investors are looking ahead to non-farm payroll data later in the day for a sense of the direction of the U.S. economy, with a strong reading seen boosting the chance of a Federal Reserve interest rate hike soon, Reuters wrote.

Friday's oil price gains may be capped by concerns of slowing global economic growth.

There is also increasing scepticism among traders that the Organization of the Petroleum Exporting Countries and other producers such as Russia will agree to freeze production at a meeting in Algeria later this month.