Oil prices rose about 1 percent on Friday, trading within a narrow range, on hopes that non-OPEC producers meeting in Vienna over the weekend would agree to cut output to bolster OPEC's own agreement to limit production.
Still, a strong U.S. dollar sapped some of the price strength, and both crude benchmarks remained nearly 2 percent below the highs reached after the Organization of the Petroleum Exporting Countries announced plans to cut production late last month.
On Saturday, oil ministers from OPEC countries will meet non-OPEC producers in Vienna to seek help in curbing a global glut.
Brent crude for February delivery was up 29 cents at $54.18 a barrel by 2:35 p.m. ET (1935 GMT), after rising 1.7 percent on Thursday. The contract hit its highest since July 2015 at $55.33 on Monday.
U.S. crude for January delivery settled up 66 cents, or 1.3 percent, at $51.50 a barrel.