Washington DC - Immigration agents will be deployed in US airports beginning Monday, aiming to alleviate soaring congestion at security screenings amid a weeks-long budget standoff over President Donald Trump's mass deportation drive, officials said.

Trump announced the extraordinary move in a social media post Sunday morning, sending officials racing to quickly develop a plan.

Tom Homan, the president's senior border aide, confirmed to CNN that Immigration and Customs Enforcement agents would be shifted from their normal duties to airports on Monday, but they would not be doing jobs they were untrained for.

Politicians Maine's Graham Platner receives "excited" endorsement from Elizabeth Warren

"I don't see an ICE agent looking at an x-ray machine, because you're not trained in that," he said on CNN's State of the Union.

Rather, the agents would help "wherever we can provide extra security," such as monitoring exits.

"We'll put together a plan today, and we'll execute tomorrow," he said.

Funding has been lapsed since February 14 for the Department of Homeland Security, as Democratic lawmakers demand reforms in the wake of Trump's deadly immigration crackdown in Minnesota.

However, DHS also oversees the Transportation Security Administration, the agency responsible for airport security screenings, meaning staff around the country have worked for weeks without pay.

Many TSA agents have begun calling out from work, prompting soaring wait times at screening lines, sometimes as high as multiple hours.

More than 300 TSA employees have quit since the shutdown began on February 14, according to the DHS, while US media reported that unscheduled absences had more than doubled.

Transportation Secretary Sean Duffy said on Sunday he thinks the situation is "going to get much worse" in the coming days.

"As it gets worse, I think that puts pressure on the Congress to come to a resolution," he told ABC's This Week.

Democrats have demanded curtailed patrols, a ban on face masks, and a requirement that ICE agents obtain a judicial warrant before entering private property.

While ICE is part of the Department of Homeland Security, it has nonetheless been able to maintain operations using funds approved by Congress last year.