US oil fell after airlines cancelled thousands of flights over the Christmas holidays amid surging COVID-19 cases, though Brent crude gained support from hopes that the Omicron variant will have limited impact on global demand.
More than 1,300 flights were cancelled by U.S. airlines on Sunday as COVID-19 reduced the number of available crews while several cruise ships had to cancel stops.
U.S. West Texas Intermediate (WTI) crude was down 91 cents, or 1.2%, at $72.88 a barrel by 1322 GMT. The U.S. market was closed on Friday for a holiday. Global benchmark Brent crude rose 17 cents, or 0.2%, to $76.31.
Brent has risen by more than 45% this year, supported by recovering demand and supply cuts by the Organization of the Petroleum Exporting Countries (OPEC) and its allies, collectively known as OPEC+.
Oil, which plunged by more than 10% on Nov. 26 when reports of a new variant first appeared, gained last week after early data suggested that Omicron could cause a milder level of illness.
Talks resume today between world powers and Iran on reviving Tehran's 2015 nuclear deal. Iran on Monday said that oil exports were the focus of the talks, which so far appear to have made little progress on boosting Iran's shipments.
Also on investors' radar is the next OPEC+ meeting on Jan. 4, in which the producer alliance will decide whether to go ahead with a planned 400,000 barrels per day (bpd) production increase in February.
OPEC+ stuck to its plans at its last meeting to boost output for January despite Omicron.
