Passengers travelling home for Christmas have been hit with disruption worldwide after airline companies cancelled more than 3,000 flights on Friday, according to a flight tracking website.

The surge of Christmas Eve cancellations came as the rapidly spreading Omicron coronavirus variant meant carriers were unable to staff their flights.

The website of the flight tracking firm FlightAware showed that 2,175 flights around the world had been scrapped on Christmas Eve, a typically heavy day for travel. Around a quarter of those were in the US. Another 1,259 Christmas Day flights were called off globally, the website said, amid a surge in Covid infections driven by Omicron.

United Airlines said rising numbers of Omicron cases had "had a direct impact on our flight crews and the people who run our operation", adding that it was contacting impacted passengers in advance of them coming to the airport.