NEW YORK (AP) – The federal agency responsible for ensuring the safety of US airports has acknowledged an increase in the number of its employees who stopped work during the partial closure of the government.

Employees of the Transportation Security Administration are expected to work without pay during the closure because their work is considered essential.

The TSA said in a statement on Friday that incoming calls that began during the holiday period had increased. The agency did not specify the number of calls from its employees, but said the calls had "a minimal impact as 51,739 employees supported the screening process." The statement states that wait times "may be affected", but so far. "Stay well in TSA standards."

"The TSA is closely monitoring the situation," the agency statement said. "The effectiveness of security will not be compromised."

The Department of Homeland Security and President Donald Trump on Saturday pushed back suggestions that incoming calls were a "disease" with significant consequences for air travel in the United States. White House officials and congressional aides were in talks Saturday to end the closure, which came in its 15th day. Negotiations are stalled over Trump's $ 5.6 billion claims to fund a wall at the US-Mexico border.

TSA spokesman Michael Bilello tweeted that 5.5% of the TSA 's workforce at the Dallas / Fort Worth International Airport had been called on Friday, compared to 3.5% at the time. a normal day. He stated that waiting times "could be affected", but that all passengers would be controlled normally.

Hydrick Thomas, president of the National Union of TSA Employees, told CNN that nearly 170 TSA employees at the John F. Kennedy Airport in New York called every day of the week. Union officials did not respond to requests for comments on Saturday.

Airport officials said there were no unusual delays in screening at JFK, O'Hare and Midway airports in Chicago, or at Miami International Airport.