Brent crude settled up 31 cents, or 0.7%, at $48.32 per barrel.

US West Texas Intermediate crude rose 41 cents, or nearly 1%, to settle at $46.29.

While some oil traders bet on more near-term gains, others were positioning to sell ahead of bearish US government oil inventory data on Wednesday.

Analyst polled by Reuters forecast a 4.5 million-barrel build in US crude stockpiles for the last week, after an unexpected 14.5 million-barrel slump the previous week, the biggest drop since 1999.

"If we get to $47.50 on WTI, I'm shorting it as it seems to be a channel top," said Phil Davis, a trader at PSW Investments in Woodland Park, New Jersey.

"Fundamentally, there's little support for crude despite its attempts to hold to a bottom channel of $45 on empty Opec talk of production cuts."

Opec is to meet with non-Opec members at an industry event in Algeria later this month to discuss a production freeze that few analysts expect will materialise.

Oil prices were down earlier on Monday, extending Friday's drop, on data from last week showing US drillers having added oil rigs for a tenth week in 11 that showed the longest stretch of builds in the oil rig count since 2011.

The market rebounded after uncertainty over a potential US Federal Reserve rate hike in September weighed on the dollar, making greenback-denominated commodities, including crude, more affordable to holders of the euro and other currencies. Equity and other risk markets soared.

Notwithstanding Monday's rebound, oil prices are still down about 5% from 8 September, partly reversing a 10% rally early this month that took to prices to around $50.

Much of that decline was pressured by the dollar's rally on speculation that the Fed may resort to a rate hike in September.

"We have shifted to a trading theme in which correlation between oil and the equities will be tightening appreciably going forward as US Fed intentions develop closer scrutiny across a range of asset classes," said Jim Ritterbusch of Chicago-based oil markets consultancy Ritterbusch & Associates.