The Supreme Court declined on Monday to review a case involving New York City’s ban on religious groups’ holding worship services in public school buildings, leaving in place a decision by a lower court that found the longstanding policy constitutional.

The decision permits Mayor Bill de Blasio to expel immediately dozens of religious organizations that have been holding worship services in city school buildings after hours and on weekends. But consistent with a pledge the mayor made during his campaign to lift the prohibition, a spokesman said on Monday that the city remained committed to allowing churches to use the schools on the same grounds as other organizations.

“Now that litigation has concluded, the city will develop rules of the road that respect the rights of both religious groups and nonparticipants,” the spokesman, Wiley Norvell, said in a statement. “While we review and revise the rules, groups currently permitted to use schools for worship will continue to be able to worship on school premises.”

The case has become the latest test of Mr. de Blasio’s approach toward church-state issues. Since taking office, the mayor has repeatedly sided with the interests of his religious constituencies over the concerns of civil libertarians, carving himself out a niche as a more religion-friendly liberal.