The West Texas Intermediate for January delivery added 73 cents, or 1 percent, to settle at 71.67 dollars a barrel on the New York Mercantile Exchange. Brent crude for February delivery increased 73 cents, or 1 percent, to close at 75.15 dollars a barrel on the London ICE Futures Exchange.
For the week, the U.S. crude benchmark jumped 8.2 percent, while Brent surged 7.5 percent, based on the front-month contracts.
It marked the sharpest weekly gain since late August for both the WTI and Brent, according to Dow Jones Market Data.
Despite the strong weekly gain, analysts warned of potential headwinds ahead.
"The risks surrounding Omicron should not be priced out entirely," as "rising infection numbers and the higher transmissibility of the new virus variant are prompting more and more countries to impose new restrictions that are unlikely to leave oil demand completely unscathed," Carsten Fritsch, energy analyst at Commerzbank Research, said Friday in a note.
"What is more, the first quarter of 2022 looks set to see a sizeable oversupply even without Omicron's impact because demand will decline for seasonal reasons while supply will increase noticeably at the same time as oil production is expanded by OPEC+ and strategic oil reserves are released in the U.S. and other leading consumer countries," he added.