Most federal workers have until tonight to decide whether to accept a buyout offer from President Donald Trump. The offers generally allow workers to resign from their positions while receiving pay through September.

The American Federation of Government Employees said it is urging federal employees not to take the offer, fearing many of the employees might not get paid.

“There is not yet any evidence the administration can or will uphold its end of the bargain, that Congress will go along with this unilateral massive restructuring, or that appropriated funds can be used this way, among other issues that have been raised,” the AFGE said in an email message to members. “We are encouraging AFGE members NOT to resign or respond to this email until you have received further information and clarification.”

The buyouts are part of President Trump's plan to overhaul government and rein in spending.

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The White House has estimated that 5% to 10% of the civilian federal workforce would take the offer. Some agencies, such as the U.S. Postal Service and some national security programs, have been exempt from the buyouts.

Scripps News has confirmed that at least 20,000 federal workers have already taken the buyout offer. The White House expects a rush of resignations in the coming hours prior to the February 6 deadline.

President Trump has also vowed to disapprove union contracts signed in the final 30 days of the Biden administration. The AFGE has told its members that the president does not have the ability to negate contracts.

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Unions representing U.S. government employees filed a lawsuit on Tuesday to block the buyout, which they claim violates federal law.

Part of the challenge workers face is whether they would make as much money in the private sector and whether they would otherwise be willing to accept sharp changes in the work environment. The Trump administration wants more workers back in the office, with fewer opportunities to work from home.