The Senate’s rule enforcer dealt a major blow to Senate Republicans Thursday morning by ruling a key Medicaid provision in the megabill that advances President Donald Trump’s legislative agenda is out of order.

Senate Parliamentarian Elizabeth MacDonough found that a provision that cracks down on states’ use of health care provider taxes to help collect additional Medicaid funding is not in keeping with the rules governing a package like the “One Big Beautiful Bill Act,” which senators are making changes to as Republicans work to meet Trump’s Fourth of July deadline for passage.

MacDonough’s ruling means that Senate Republicans will need to retool the provision or scrap it entirely if they want to move forward with attempting to pass the bill using only GOP votes.

The ruling is a major setback for Republican leadership, who are under pressure to expeditiously move it to the Senate floor to meet the July deadline. This ruling will require potentially major reworks of the bill with relatively little time to accomplish them.