Oil prices eased on Friday but were set for a sixth week of gains, as the rollout of novel coronavirus vaccination programmes fed hopes that demand for fuel would rebound next year.
Brent was down 19 cents or 0.4% at $50.06 a barrel by 0946 GMT, after rising above $51 a barrel on Thursday to an early-March high.
U.S. oil was down 11 cents, or 0.2%, at $46.67 a barrel, having risen almost 3% in the previous session.
Promising vaccine trials helped lift some gloom over record increases in the number of new coronavirus infections and deaths around the world.
Britain began inoculations this week and the United States could start vaccinations as early as the coming weekend, while Canada on Wednesday approved its first vaccine with initial shots due from next week.
"The vaccine optimism ... seems to continue unscathed due to the back-to-back approvals vaccines are getting and the quicker-than-previously-thought rollout of the first campaigns in key markets," Rystad Energy analyst Paola Rodriguez-Masiu said.
Outside advisers for the U.S. Food and Drug Administration have voted to endorse emergency use of Pfizer's vaccine, paving the way for the agency to authorise its use to inoculate a nation that has lost more than 285,000 lives to COVID-19.
A big jump in U.S. crude stockpiles last week served as a reminder that there is still plenty of supply available, but it was all but ignored as bulls ran through the market this week. [EIA/S]
"The long-awaited rollout of vaccination programmes provided ample bullish fodder in the face of rising US oil inventories," brokerage PVM's Stephen Brennock said.
Signs that Asian demand is strong have also encouraged the market with India's biggest refiner saying that all of its nine units were operating at 100% capacity for the first time since early this year.
(Additional reporting by Aaron Sheldrick in Tokyo; Editing by Robert Birsel)
