The Supreme Court acted Monday to keep Texas' 19 abortion clinics open, amid a legal fight that threatens to close more than half of them.

The justices voted 5-4 to grant an emergency appeal from the clinics after a federal appeals court upheld new clinic regulations and refused to keep them on hold while the clinics appealed to the Supreme Court.

The Supreme Court order will remain in effect at least until the court decides whether to hear the clinics' appeal of the lower court ruling, not before the fall.

The court's decision to block the regulations is a strong indication that the justices will hear the full appeal, which could be the biggest abortion case at the Supreme Court in nearly 25 years.

If the court steps in, the hearing and the eventual ruling would come amid the 2016 presidential campaign.

Chief Justice John Roberts and Justices Samuel Alito, Antonin Scalia and Clarence Thomas would have allowed the state to move ahead with regulations requiring abortion facilities to be constructed like surgical centers. Doctors at all clinics also would be required to have admitting privileges at a local hospital.

The clinics said enforcing the new regulations would lead to a second major wave of clinic closures statewide since the law was enacted in 2013. Texas had 41 abortion clinics in 2012; 19 remain.