This is a file photo of a Delta Air Lines plane.

China has ordered the cancellation of more than two dozen flights from the United States amid a surge of the highly contagious Omicron variant of the coronavirus in the US.

On Tuesday, the Civil Aviation Administration of China (CAAC) mandated the cancellation of 22 scheduled US passenger airline flights for Shanghai.

Delta Air Lines said it had cancelled Detroit-to-Shanghai flights last Friday. The CAAC said it would cancel another two Delta flights from Detroit to Shanghai and another six Delta flights from Seattle to Shanghai next week, bringing the total cancellations for the airline to 10.

Delta said it was also set to cancel inbound service on certain China flights for January 14.

China has in recent weeks detected numerous COVID-19 cases among passengers arriving from the US.

The US Transportation Department (USDOT) did not immediately comment on the cancellations, which come as the country is facing a surge in infections caused by Omicron.

The number of people hospitalized with the infection in the US has surpassed last winter�s peak. As of Monday, 132,646 people were hospitalized with COVID-19, surpassing the record of 132,051 set in January 2021.

The seven-day average for new cases has doubled in the last 10 days to 704,000.

Public health officials, however, claim that caseloads were of limited significance because Omicron is milder than Delta and other variants.

But the current surge has overwhelmed hospitals across the US.

Hospitalizations are considered as one of the most reliable measures of the severity of the pandemic.