NATIONWIDE — President Donald Trump threatened to deploy Immigration and Customs Enforcement agents to airports across the United States during the ongoing Department of Homeland Security shutdown.

"If the Radical Left Democrats don't immediately sign an agreement to let our Country, in particular, our Airports, be FREE and SAFE again, I will move our brilliant and patriotic ICE Agents to the Airports where they will do Security like no one has ever seen before," Trump said.

Senate Democrats voted down Republicans' effort to pass a bill to fund the Department of Homeland Security, which has been partially shut down since mid-February. Transportation Security Administration officers who conduct security checks at U.S. airports have gone unpaid due to the shutdown. The shutdown has led to mass callouts among TSA officers and caused lengthy security lines at airports.

In February, Senate Democrats vowed to shut down the Department of Homeland Security until Republicans agreed to require ICE agents to wear identification and ban face coverings. ICE is not affected by the DHS shutdown and received an additional $75 billion in funding from the major legislative package passed and signed into law last year.

Negotiators on Capitol Hill met in recent discussions to work on ending the shutdown. Republicans offered Democrats a new proposal including body cameras for ICE agents, additional training, and restrictions on arrests in sensitive areas such as churches, hospitals, and schools.

Tom Homan met with some Senate lawmakers in recent discussions as part of the negotiations. "I think the Democrats need to come back to us now and talk to us about what they're willing to do," said Senator John Hoeven.

Senators on a key committee considered the nomination of Markwayne Mullin to lead the Department of Homeland Security. Trump said that Homeland Security Secretary Kristi Noem would step down at the end of March and that he would nominate Mullin as the next Secretary of Homeland Security.