"Winter weather in parts of the US and the Omicron variant continued to affect Delta’s holiday weekend flight schedule," a spokesperson said.
The company was working to "reroute and substitute aircraft and crew to get customers where they want to be as quickly and safely as possible".
Where that was not possible, it was co-ordinating with customers on the next available flight, the spokesperson said.
Globally, FlightAware data showed that nearly 2,150 flights were cancelled on Sunday and 5,798 were delayed.
Omicron was first detected in November and accounts for nearly three-quarters of US cases and as many as 90% in some areas, such as the Eastern Seaboard. The average number of new US coronavirus cases has increased by 45% to 179,000 per day over the past week, according to a Reuters tally.
While research suggests Omicron produces milder illness and a lower rate of hospitalisation than previous variants of Covid-19, health officials have maintained a cautious note on the outlook.
Reuters
Omicron grounds hundreds more US flights over Christmas weekend
US airlines cancelled hundreds of flights for the third day in a row on Sunday as surging Covid-19 infections, due to the Omicron variant, grounded crews and forced tens of thousands of Christmas weekend travellers to change their plans.
Commercial airlines cancelled 656 flights within, into or out of the US on Sunday, down from nearly 1,000 on Christmas day and almost 700 on Christmas eve, according to flight-tracking website FlightAware.com.
Further cancellations were likely and more than 920 flights were delayed.
The Christmas holidays are peak time for air travel, but the rapid spread of the Omicron variant has led to a sharp increase in Covid-19 infections, forcing airlines to cancel flights with pilots and crew needing to be quarantined.
Delta Air Lines expected more than 300 of its flights to be cancelled on Sunday.
"Winter weather in parts of the US and the Omicron variant continued to affect Delta’s holiday weekend flight schedule," a spokesperson said.
The company was working to "reroute and substitute aircraft and crew to get customers where they want to be as quickly and safely as possible".
Where that was not possible, it was co-ordinating with customers on the next available flight, the spokesperson said.
Globally, FlightAware data showed that nearly 2,150 flights were cancelled on Sunday and 5,798 were delayed.
Omicron was first detected in November and accounts for nearly three-quarters of US cases and as many as 90% in some areas, such as the Eastern Seaboard. The average number of new US coronavirus cases has increased by 45% to 179,000 per day over the past week, according to a Reuters tally.
While research suggests Omicron produces milder illness and a lower rate of hospitalisation than previous variants of Covid-19, health officials have maintained a cautious note on the outlook.
Reuters
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