Brent futures last cleared $50 a barrel on July 5.
Futures were little changed in NY after advancing more than 12 percent over the previous five sessions.
United States oil inventories fell 2.5 million barrels last week, surprising analysts who had expected a build of 522,000 barrels, the Energy Information Administration (EIA) said in its weekly report on Wednesday, Xinhua news agency reported. "Prices are only marginally above where they were when the group met in Doha in April and couldn't agree to a deal", ANZ analysts said in a note.
Elsewhere, investors reacted to news out of the Middle East after Reuters reported that Saudi Arabia could increase production even further heading into a closely-watched meeting in Algeria next month.
"A solid draw to crude stocks, helped in large part by another large draw to the West Coast, has been a supportive element, as has a solid draw to gasoline". "Yesterday's weekly oil inventory report deviated hugely from the consensus".
On Thursday, West Texas Intermediate crude futures in NY rose 2.8% to $48.11 per barrel, a six-week high. Total volume traded was about 14 percent below the 100-day average.
Later around 1230 GMT, Brent North Sea crude for delivery in October was up two cents at $49.87 a barrel following some profit-taking.
Congress lifted the ban on exporting USA crude oil in the omnibus spending bill passed last December, allowing crude oil to be exported to countries outside of North America for the first time since the mid-1970s.
"We remain skeptical that renewed talks of a production freeze by OPEC and other large producers will lead to a deal".
USA crude wavered in a volatile session on Wednesday but crept to fresh five-week highs, as investors reacted to an unexpected decline in domestic stockpiles last week along with further signals that Saudi Arabia could ramp up production to a new all-time record in August. After Tuesday's market close, the American Petroleum Institute (API) reported estimates that US gasoline inventories had risen 2.2 million barrels for the week ending August 12.