A late night ruling on Tuesday from the New Orleans-based 5th U.S. Circuit Court of Appeals halted the enforcement of the law ahead of oral arguments on the issue scheduled for Wednesday.

The legal back and forth in the case has caused uncertainty about the future of the controversial measure put in place by Republican Governor of Texas Greg Abbott. The lawis opposed by the democratic administration of President Joe Bidenwhich says it would impede the federal government from enforcing immigration laws.

Abbott last December signed the law, known as SB 4, authorizing state law enforcement to arrest people suspected of entering the U.S. illegally, giving local officers powers long delegated to the federal government. Abbott said the law was needed due to Biden’s failure to enforce federal laws criminalizing illegal entry or re-entry.

Republicans have sharply criticized the Democratic president’s handling of the record numbers of migrants caught illegally crossing the U.S.-Mexico border. Abbott and other Republicans favor the restrictive policies of former President Donald Trump, their party’s candidate challenging Biden in the Nov. 5 U.S. election.

White House Press Secretary Karine Jean-Pierre said the Texas law will “sow chaos and confusion at our southern border.”

The Justice Department sued in January to block the measure, originally set to take effect on March 5. The administration said the law violates the U.S. Constitution and federal law by interfering with the U.S. government’s power to regulate immigration as well as running afoul of a 2012 Supreme Court precedent.

The Texas law made illegal entry or re-entry into Texas a state crime, with penalties ranging from 180 days in jail to 20 years in prison. It requires Texas magistrate judges to order migrants to return to Mexico, with up to 20-year sentences for those who refuse to comply.

Mexico, however, said on Tuesday it would not accept those repatriated by the state of Texas.

Texas-based U.S. District judge David Ezra on Feb. 29 sided with the Biden administration and agreed to preliminarily block Texas officials from enforcing the law, saying it “threatens the fundamental notion that the United States must regulate immigration with one voice.”

But the 5th Circuit paused Ezra’s ruling in an order that would have let the law take effect on March 10, prompting the administration to file an emergency request to the Supreme Court. Justice Samuel Alito, acting for the Supreme Court, on March 4 had halted the 5th Circuit ruling – and thus the law – from taking effect, giving the justices more time to consider the matter.

The Supreme Court on Tuesday then ruled 6-3, along ideological lines, to allow the law to take effect before the 5th Circuit’s decision.

The 5th Circuit panel, in a 2-1 vote, lifted the administrative stay ahead of arguments on whether to once again put on hold the lower-court injunction while Texas pursues an appeal.

The majority in the appeals court’s order included Chief U.S. Circuit Judge Priscilla Richman, an appointee of Republican former President George W. Bush, and U.S. Circuit Judge Irma Carrillo Ramirez, a Biden appointee. U.S. Circuit Judge Andrew Oldham, a conservative appointee of Republican former President Donald Trump, dissented.

(Reporting by John Kruzel in Washington and Andrew Chung in New York; Additional reporting by Mica Rosenberg in New York, Kristina Cooke in San Francisco, Kylie Madry in Mexico City and Nate Raymond in Boston; Editing by Will Dunham, David Gregorio and Lincoln Feast.)