Donald Trump said Saturday he will deploy Immigration and Customs Enforcement agents to US airports on Monday if an agreement isn’t reached to fund the Department of Homeland Security amid a partial government shutdown.

It is unclear what function the ICE agents would perform since they’re not trained in airport security screening. TSA screeners have a several months-long training period before they’re on the job, though airline employees and private security companies have partnered on line controlling and guarding exit doors.

The agents could potentially help in more limited roles — like managing lines, directing passengers or helping move people through the checkpoint process — to free up trained TSA officers for critical security functions.