The Senate failed for a fourth time to advance a $39.7bn (£25.7bn) bill to fund the Department of Homeland Security (DHS) that includes Republican-authored provisions to block President Barack Obama's recent immigration orders that lift the threat of deportation from millions of undocumented immigrants.
Senate Democrats blocked the measure and repeated their call for a "clean" bill free of immigration restrictions. Funding for the department, which spearheads domestic counter-terrorism efforts and secures US borders, will be cut off at 11.59pm on 27 February unless Congress renews it.
If Homeland Security spending is cut off, the department's essential protective staff would stay on the job, but there would be no money to pay them until new funding is approved.
"The Coast Guard is on the job. They are working in the cold, they are working in the wind, they are breaking up ice in not only Maryland, but all over to these frozen ports, and what do we say? Good job guys, there they are on TV and we love you, but we might not pay you. What is this? They are out there saving lives and we are playing parliamentary ping-pong," said Democratic Senator from Maryland Barbara Mikulski.
After the failed vote, Senate Majority Leader Mitch McConnell unveiled a stand-alone bill to block the president's November 2014 order lifting the threat of deportation against millions of undocumented immigrants.
While the path forward for Homeland Security remains unclear, several Republican senators said a stop-gap funding extension of one or two months, called a continuing resolution (CR), was under discussion and they would likely support it.
That would allow the department to continue full operations and pay its 230,000 employees while a federal court challenge to Obama's immigration actions plays out.