A top TSA union leader warned Thursday that airport security risks linked to the ongoing government shutdown are set to "get worse," pointing to a critical issue he says has largely gone unaddressed.

"TSA has been under a . . . hiring freeze since last year, so when you look at what we had in the fall, the 50 days that we had off of shutdown, we have people that left, that retired," TSA union leader George Borek told "Varney & Co."

"The acting director yesterday said we had 400 some odd agents that so far have signaled that they're leaving," he added.

"That number is going to grow exponentially."

TSA OFFICERS SKIP WORK AS PAYCHECKS STOP DURING SHUTDOWN, AIRPORTS FACE CHAOS NATIONWIDE

Borek said the problem will only exacerbate as the agency struggles to replace those who left, noting the length of time it takes to get agents certified for checkpoints.

That struggle could be compounded as the busiest travel season of the year approaches and as an anticipated uptick in international flyers arrive in the U.S. for the FIFA World Cup this summer.

‘EMPTY REFRIGERATORS AND EVICTION NOTICES’: TSA UNION LEADERS DEMAND END TO DHS SHUTDOWN

"The other part is — what happens once this is settled?" he asked.

"Are we going to continue having the resources that we need in order to do our jobs effectively?"

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TSA agents have gone unpaid since the onset of a partial government shutdown, forcing airports like Hartsfield-Jackson in Atlanta to find ways to mitigate the issues some agents are facing financially.

The dispute stems from a political standoff in Washington over funding for the Department of Homeland Security, which has created concerns of potential security loopholes as the government shutdown drags on with no end in sight.