Newark airport has been branded unsafe for travellers after air traffic controllers apparently lost contact with planes for more than a minute.

The New Jersey airport has been hit by days’ worth of flight delays and cancellations, which officials have blamed on staffing shortages and outdated technology.

Last week, air traffic controllers were reportedly unable to “see, hear or talk” to planes heading into and out of Newark for approximately 90 seconds.

One air traffic control worker warned travellers to “avoid Newark at all costs”, while United Airlines is cutting dozens of Newark flights per day to “protect customers”.

The US has faced a series of aviation disasters in recent months, including a crash involving an American Airlines jet and a military helicopter that killed 67 people as it approached a Washington DC airport.

Newark Liberty International Airport, which is one of the busiest travel hubs in the US and handles millions of passengers a year, had 163 flight cancellations in 24 hours as of Monday afternoon, according to FlightAware.

On April 28, air traffic controllers responsible for sequencing aircraft in and out of Newark airport are said to have lost contact with planes for 90 seconds, Bloomberg reported.

They “temporarily lost radar and communications with the aircraft under their control, unable to see, hear, or talk to them”, the National Air Traffic Controllers Association union said in a statement to The Telegraph.

It is unclear what specifically caused the blackout, but the Federal Aviation Administration (FAA) appeared to suggest that the “antiquated air traffic control system” could be to blame.

Air traffic controllers subsequently took a leave of absence after experiencing the “traumatic event”, the union said.