The US Federal Aviation Administration has halted all departing flights in the country “due ⁠to extraordinary circumstances and safety reasons” after the agency earlier reported serious air traffic control communications issues.

The announcement means flights ⁠in the air ​may ⁠land, but flights on the ground cannot take off.

Shortly before the ⁠announcement, the FAA halted traffic in Chicago ​due ⁠to air traffic ‌control communications issues. The agency said, “All departing traffic should remain groundstopped until further ‌notice.” The FAA said international ‌flights will be managed on a case-by-case basis.

The US Transportation Secretary Sean Duffy confirmed that the stop was due to a communication issue affecting all of the country’s air traffic control centres.

He added that FAA technicians are investigating.

Airline officials said the FAA had not indicated when the ground stop might be lifted, but there were preliminary indications the communications issues were improving in some places.

The world’s busiest airspace has ‌experienced setbacks in recent years that have disrupted flights and ‌risked safety. In January 2025, a midair collision at Ronald Reagan Washington National Airport killed 67 people. 

The flight tracking website Flightradar24 has 3,100 flights currently en route to US airports.

It is not clear how the communication issue will affect inbound flights.

The Homeland Security Secretary Markwayne Mullin repeatedly told reporters that the situation “isn’t another 9/11”.

He said that President Donald Trump was briefed on the situation and ‌all flights were ​accounted for.

This is only the second time the US has grounded its departing flights since the September 11 attacks in 2001. A ground stop was issued for less than two hours in January 2023 when a pilot notification system went down.

Last year, Congress ​approved $12.5 billion to fix the ‌FAA’s aging communications system, ⁠and on Friday the FAA ⁠and White House asked Congress for another $30.1 billion to ‌address ​other issues.

The outage comes amid heightened concern ​about aviation security worldwide after a wave of hoax bomb threats this month disrupted dozens ‌of passenger flights across Europe, forcing unscheduled landings ⁠and prompting fighter jets to escort or intercept aircraft.

There was no immediate indication the ⁠US communications failure was related to those incidents or caused by a cyberattack.

The US National Weather Service also ⁠said on Friday that it was experiencing ⁠nationwide ​internet ⁠and communications problems ⁠that could ​prevent ⁠users from ‌accessing products on its ‌websites or ‌cause outdated information ⁠to be displayed.

There was no immediate indication the ‌two incidents were connected.

This is a breaking story and is being updated