More than 2,100 US flights cancelled in a day as government shutdown persists

More than 2,100 domestic flights have been cancelled in the United States in a single day and the country's transport secretary says air traffic could "slow to a trickle" ahead of the Thanksgiving holiday period if the government shutdown persists.

A reduction of up to 10 per cent of commercial flight services at 40 of the nation's busiest airports has continued through a third day, after the Federal Aviation Administration (FAA) ordered the cuts as some air traffic controllers, who have gone unpaid for nearly a month, did not show up for work.

In addition to the cancellations on Sunday, local time, some 7,000 flight delays were reported, according to FlightAware, a website that tracks air travel disruptions.

Those figures added to the more than 1,000 flights cancelled Friday and more t