The Supreme Court on Friday limited the ability of lower-court judges to block executive branch policies nationwide, opening the door for a majority of states to at least temporarily enforce President Trump’s executive order ending birthright citizenship.

With their decision, the justices appeared to upend the ability of single federal judges to freeze policies across the country. The powerful legal tool, known as a nationwide injunction, had been used frequently in recent years to block policies put in place by Democratic and Republican administrations and gave rise to charges of judge shopping.

But the immediate effect of the 6-to-3 decision, which was written by Justice Amy Coney Barrett and split along ideological lines, was to give Mr. Trump a major if perhaps temporary victory in his efforts to redefine citizenship in the United States.

The justices did not rule on the constitutionality of the executive order issued by Mr. Trump in January, which seeks to end the practice of automatically granting citizenship to anyone born in the United States, even if the parents are not citizens. That question is likely to come back to the Supreme Court, perhaps as soon as next year.

In the meantime, the decision cleared the way for the executive order to go into effect in the 28 states that have not challenged it, which could create a patchwork system in which the rules for citizenship are different in different parts of the country.

Still, the Supreme Court ruling will not take effect for 30 days. And the justices laid out a potential path for challengers, saying that district court judges could consider whether to take up class-action suits seeking to bar enforcement of the executive order on a statewide, regional or even national basis.