A coalition of nonprofits and public health advocates is asking a federal judge for an emergency order to block President Donald Trump from imposing a sweeping plan to halt all federal aid programs.

“Given the few hours that remain before federal grantees are thrown into disarray, Plaintiffs file this Complaint and seek a temporary restraining order to maintain the status quo until the Court has an opportunity to more fully consider the illegality of the Trump administration’s] actions,” the groups wrote in a 20-page lawsuit.

The legal effort follows an internal memo sent by the acting head of Trump’s Office of Management and Budget calling for a halt to all federal aid spending except for Medicare and Social Security. The freeze is set to go into effect at 5 p.m. Eastern on Tuesday. The order appears to run afoul of federal law requiring the administration to spend funds appropriated by Congress, a statute Trump has assailed as unconstitutional.

The groups — including the National Council of Nonprofits, the American Public Health Association and the Main Street Alliance — say the order appears to violate the law on numerous fronts.

“Halting this funding would lead to pauses of important community programs, food and safety assistance, and lifesaving research, among other things: even a short pause could be devastating, decimating organizations, costing lives, and leaving neighbors without the services they need,” the groups say in the lawsuit.