A group of Texas Republicans in Congress vowed Thursday to halt federal funding for the Department of Homeland Security until Secretary Alejandro Mayorkas is removed from office.

“Under no circumstances am I going to support any appropriation to the Department of Homeland Security, any continuing resolution at all,” U.S. Rep. Chip Roy, R-Austin, said at a news conference at the Capitol. “I will use every tool at my disposal to thwart giving another dollar to this secretary to leave Texas exposed.”

It’s an amplified threat as Congress works through the funding process to keep the government operating into the next fiscal year. Failure to approve funding could lead to a federal shutdown — an outcome some far-right members have said they are prepared to precipitate.