LOS ANGELES - US Secretary of Energy Chris Wright said Monday that approximately 1,400 employees with the National Nuclear Security Administration (NNSA) have received furlough notices across the country as the federal government shutdown approached its third week.

"Today is the day our ability to deploy funds to pay those workers ended," Wright said during a press conference at the Nevada National Security Site in North Las Vegas, noting that this marked the first furlough in the NNSA's 25-year history.

The Department of Energy confirmed the figures in a statement, adding that fewer than 400 federal workers remain on duty at the agency.

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"This should not happen, but this was as long as we can stretch the funding for the federal workers," Wright said, warning that if the shutdown continued, contractors still on the job could also be furloughed and may begin seeking other employment.

Emphasizing the importance of the agency's mission, Wright said, "The humans working on it are critical. We need to open the federal government as quickly as we can," cautioning that modernization efforts and testing could be delayed due to the shutdown.

Local media reported that the furloughs also impacted some of the more than 3,000 contractors working for the NNSA in Nevada.

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Local news outlet KCRA reported that some experts expressed concern that furloughs could undermine safeguards for nuclear materials and waste, potentially posing risks to public safety and national security.

The NNSA is a federal agency under the Department of Energy tasked with maintaining the US nuclear arsenal and safeguarding national security through the military application of nuclear science.