The United States on Sunday cancelled more than 2,700 flights due to Omicron-related disruptions.
According to a running tally on flight-tracking website FlightAware.com, 9,230 flights within the United States or entering or departing it were either canceled or delayed on Saturday alone.
As per the site, the worst affected US airline was SkyWest, which had to cancel 23 percent of its flight schedule.
Adding to the impact of a massive spike in Covid-19 infections fuelled by the Omicron variant is bad weather in parts of the country. Chicago has been particularly hard-hit because of a snowstorm.
The global air travel industry is still reeling from the highly contagious Omicron variant.
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The Christmas holidays are typically a peak time for air travel, but the rapid spread of the highly transmissible Omicron variant has led to a sharp increase in COVID-19 infections, forcing airlines to cancel flights as pilots and crew quarantine.
The sudden arrival of Omicron has brought record-setting case counts to countries around the world.
Global coronavirus infections hit a record high over the past seven-day period, with an average of just over a million cases detected a day worldwide between December 24 and 30, up some 100,000 on the previous peak.
(With inputs from agencies)
