A federal judge in New Hampshire issued a ruling Thursday prohibiting President Donald Trump’s executive order ending birthright citizenship from taking effect anywhere in the U.S.

Judge Joseph LaPlante issued a preliminary injunction blocking Trump’s order and certified a class action lawsuit including all children who will be affected. The order, which followed an hour-long hearing, included a seven-day stay to allow for appeal.

The judge’s decision puts the birthright citizenship issue on a fast track to return to the Supreme Court. The justices could be asked to rule whether the order complies with their decision last month that limited judges’ authority to issue nationwide injunctions. The Supreme Court said district judges generally can’t issue nationwide, or universal, injunctions. But it didn’t rule out whether judges could accomplish much the same thing by a different legal means, a class action.

At issue is the Constitution’s 14th Amendment, which states: “All persons born or naturalized in the United States and subject to the jurisdiction thereof, are citizens of the United States.” The Trump administration says the phrase “subject to the jurisdiction thereof” means the U.S. can deny citizenship to babies born to women in the country illegally, ending what has been seen as an intrinsic part of U.S. law for more than a century.