The delays are the latest problem to plague the airport, where radar and radio communications have recently malfunctioned.
Most flights destined for Newark Liberty International Airport were being delayed at their origin airports by more than an hour and 40 minutes on Monday because of a shortfall in air traffic control staffing.
The Federal Aviation Administration said in an advisory that it was delaying the incoming flights from all U.S. airports and some in Canada. The agency did not immediately respond to a request for comment.
While incoming flights were being held, few flights to or from Newark had been canceled, according to FlightAware, a flight tracking firm. Delays can have cascading effects on flights around the world.
Monday’s delay is the latest in a string of setbacks for Newark, one of the nation’s busiest airports and a large hub for United Airlines. On Friday, an air traffic control facility that guides planes at the airport had a brief radar outage. A similar outage earlier in the month had left controllers unable to communicate with pilots for about 90 seconds.
The F.A.A. briefly slowed flights to and from Newark again early on Sunday because of a telecommunications problem at the facility. That day, the transportation secretary, Sean Duffy, said on NBC’s “Meet the Press” that he plans to slow flights at the airport to better address the lengthy delays it has seen in recent weeks.
The Trump administration has also promised to install new fiber-optic cables connecting the airport and the facility, which was recently moved from Long Island in New York, to Philadelphia.
In a news conference on Monday, Mr. Duffy sought to deflect blame, saying that the previous administration had “bungled” the move to Philadelphia.
This is a developing story. Check back for updates.