Oil held gains near $57 a barrel as US drillers targeting crude reduced the rig count for the first time in four weeks.
Futures were little changed in New York after rising 0.5% on Friday. Shale explorers trimmed the number of rigs by four to 747 last week, according to Baker Hughes data.
Hedge funds have boosted bets on rising prices to a record for Brent crude and to near a nine-month high for West Texas Intermediate, exchange and government data showed last week.
Oil is set for a second yearly gain as the Organisation of Petroleum Exporting Countries (Opec) and its allies trim production to drain a global glut. While the group has extended cuts through the end of 2018, it faces rising output from the US, which is forecast to surge next year to a record 10 million barrels a day.
"Oil should remain a little bit stronger going into the end of the year,” said David Lennox, a commodity analyst at Fat Prophets in Sydney.
"Key things to watch in 2018 are Opec compliance and better demand across the globe. The only headwind is US production - that’s going to keep the oil price in check."
WTI for January delivery, which expires Tuesday, rose 9 cents to $57.39 a barrel on the New York Mercantile Exchange as of 1pm in Hong Kong. Total volume traded was about 46 percent below the 100-day average.
Prices gained 26 cents on Friday, trimming the third weekly loss to 0.1%.
Brent for February settlement was up 14 cents at $63.37 a barrel on the London-based ICE Futures Europe exchange. Prices fell 0.3% last week.
The global benchmark traded at a premium of $5.96 to February WTI.
The Brent net-long position - the difference between bets on a price increase and wagers on a drop - rose 1.8% to a record 544.051 contracts, according to data from ICE Futures Europe.
Money managers cut their WTI net-long position by 0.4% to 390.874 futures and options in the week ended December 12, the US Commodity Futures Trading Commission said on Friday.
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