United Airlines executives are trying to reassure their customers it is safe to fly at Newark Liberty International Airport, despite widespread cancellations and air traffic control issues continuing to spark concerns.

Travel woes at Newark Airport continued Monday after a weekend featuring another radar outage, a ground stop and dozens of flight cancellations and delays. The FAA announced Newark was operating on a ground delay program,

Transportation Secretary Sean Duffy released a four-point plan to address the failing infrastructure at Newark Liberty Airport.

The recent chronic delays and cancellations at New Jersey's largest airport have highlighted the shortage of air traffic controllers and the aging equipment they use, which President Donald Trump's administration wants to replace.

United Airlines CEO Scott Kirby reassured customers that Newark Airport is "absolutely safe" for travel in an email sent on Monday.

"We continue to urge the FAA to address ongoing staffing shortages," a Port Authority spokesperson told Newsweek.

The delays continued at Newark Liberty International Airport on Monday evening with average backups of more than 1 1/2 hours.

The Federal Aviation Administration (FAA) briefly slowed air traffic at Newark Liberty International Airport on Sunday because a new telecommunications issue affected the Philadelphia facility