WASHINGTON — The Department of Homeland Security said Friday that it is ending the collective bargaining agreement with the tens of thousands of frontline employees at the Transportation Security Administration, marking a major attack on worker rights under the Trump administration.

The department, in a statement announcing the termination, criticized the union whose staffers are responsible for keeping weapons off of airplanes and protecting air travel. The department said that poor performers were being allowed to stay on the job and that the agreement was hindering the ability of the organization “to safeguard our transportation systems and keep Americans safe” — an assessment that faced immediate pushback from a top Democrat in Congress.

“This action will ensure Americans will have a more effective and modernized workforces across the nation’s transportation networks,” the agency said in a statement. “TSA is renewing its commitment to providing a quick and secure travel process for Americans.”

The TSA has about 50,000 staffers — called transportation safety officers — who are the ones responsible for staffing airports around the country and checking to make sure that hundreds of thousands of passengers a day do not carry any weapons or explosives into the secure areas of airports.

The decision to end the collective bargaining agreement comes after President Donald Trump’s administration pushed out TSA Administrator David Pekoske the day the Republican president was sworn into office. The agency does not currently have an administrator or a deputy administrator.

The end of the collective bargaining agreement was immediately slammed by the top Democrat on the Homeland Security committee in Congress, Rep. Bennie G. Thompson of Mississippi, who praised the work of TSA staffers in protecting air travel.

“Attempting to negate their legally binding collective bargaining agreement now makes zero sense — it will only reduce morale and hamper the workforce,” Thompson said. “Since the Biden Administration provided pay increases and a new collective bargaining contract to the workforce, TSA’s attrition rates have plummeted.”

Thompson also criticized the Homeland Security press release, saying the department was using “flat out wrong anti-union talking points.” He said the real aim was “diminishing” the workforce so “they can transform it in the mold of Project 2025.”

Project 2025 was the conservative governing blueprint that Trump insisted during the 2024 campaign was not part of his agenda. Project 2025 calls for immediately ending the TSA union and eventually privatizing the entire agency.

The union said it would have a statement soon.