CHICAGO — The Federal Aviation Administration says it will close 149 air traffic control towers at small airports around the country because of federal budget cuts.

The agency announced the decision Friday, a month after it released a preliminary list of facilities that could be closed.

All of the affected airports will remain open. Pilots will be left to coordinate takeoffs and landings among themselves over a shared radio frequency with no help from ground controllers. That’s something they are trained to do, but airport directors have raised concerns about the potential impact on safety.

In an accompanying statement, FAA Administrator Michael Huerta says the agency will take steps to ensure safe operations at the affected airports.