President Donald Trump has threatened to send federal immigration agents to airports across the U.S. amid an ongoing dispute between Senate Republicans and Democrats over funding for the Department of Homeland Security (DHS). This comes after Democrats voted down Republicans' attempts to pass a bill to fund DHS, which has been partially shut down since mid-February. The shutdown has led to Transportation Security Agency officers, who perform security checks at U.K. airports, to go unpaid, leading to call outs and lengthy security lines at airports across America. ICE, another DHS agency, is unaffected due to the ongoing shutdown. This comes as bipartisan negotiators are working to end the shutdown and consider new proposals from Democrats.