Oil prices rose about 1 percent on Friday on hopes that non-OPEC producers meeting in Vienna over the weekend would agree to output restrictions following limits OPEC announced last week to curb an oil glut, Reuters reported.
Both Brent and U.S crude futures, however, notched their first weekly loss in four weeks.
A strong U.S. dollar .DXY that makes greenback-denominated crude more expensive to many buyers, pressured oil, keeping both benchmarks nearly 2 percent below the highs reached late last month after the Organization of the Petroleum Exporting Countries (OPEC) announced plans to cut production.
On Saturday, OPEC oil ministers will meet non-OPEC producers in Vienna to seek help in curbing a global glut.
Saudi Energy Minister Khalid Al-Falih said he was very optimistic about meeting with non-OPEC producers on Saturday and expected 10 to 11 Non-OPEC countries to contribute specific numbers during the meeting.
Russia plans to hold more talks on Friday with some OPEC and non-OPEC nations about unresolved issues, two Russian sources told Reuters. However, Energy Minister Alexander Novak said he expected non-OPEC oil producers to fully contribute to production cuts agreed earlier with OPEC.
Price gains were slightly pared after data showed U.S. energy companies this week added 21 oil drilling rigs, the biggest weekly increase since July 2015.
U.S. crude's West Texas Intermediate (WTI) futures CLc1 ended the session at $51.50 a barrel, up 66 cents or 1.30 percent, after trading narrowly between $50.86 and $51.66.
Brent crude LCOc1 closed up 44 cents, or 0.82 percent, at $54.33 per barrel after dealing between $53.77 and $54.46.