The Biden administration on Tuesday struck down a last-minute union contract the Trump administration signed with Immigration and Customs Enforcement (ICE) employees, squashing a deal that would have allowed the union to stall the administration’s immigration policies.

The agreement, signed by former acting Deputy Secretary of Homeland Security Ken Cuccinelli, forced the administration to get the blessing of the union before enacting policy changes.

ICE leaders disapproved the agreement just days before it was set to formally take effect.

“We’re gratified that the agency acted before it was too late. And too late would have been any time after Feb. 18 so literally just days away,” said David Seide, an attorney representing a whistleblower who first flagged the union agreement.

Without agency action, the agreement would automatically become ratified, requiring the agency to seek “prior affirmative consent” from the 7,000-member National ICE Council before changing working conditions, something that includes hours and compensation as well as policy decisions.

Seide said the agreement effectively gave the union “veto power” over many of the Biden administration's immigration plans as it seeks to roll back Trump’s legacy.

"As part of routine process and provided for by statute, the department conducted a review of the terms of the agreement and determined that it was not negotiated in the interest of DHS and has been disapproved because it is not in accordance with applicable law," a Department of Homeland Security (DHS) spokesperson told CBS News on Tuesday.

The agreement had surprised even former Trump administration officials, who described it as a bad deal for management.

“It was not good for the agency because management lost a lot of rights on how they run the agency,” Tom Homan, who led ICE in the early days of the Trump administration, previously told The Hill.

“To run an agency this big efficiently and effectively, management needs to make decisions and can’t be hamstrung by a union that’s going to slow down or impede quick action by the agency,” he added.

The agreement contained other unusual aspects, including a provision that bars any legal challenges to the contract for another eight years — a move that would kick any negotiations beyond the reach of the Biden administration.

It also gives the ICE union, which twice endorsed Trump, far more official hours to work on union activity than any other DHS agency union.

The ICE union did not immediately respond to request for comment.

It’s also not clear that Cuccinelli even had the authority to sign the agreement. A federal court in March found that his lengthy status as an acting official violated federal vacancy laws and invalidated some of his other official decisions.