The largest public school system in the U.S. will observe the two most important Muslim holidays starting next fall.

Under the new policy, which was hailed Wednesday by Islamic leaders in New York City, the city’s 1.1 million-pupil public school system will close Sept. 24 for Eid al-Adha and the holiday of Eid al-Fitr, which will be observed during the summer school session next year.

"Hundreds of thousands of Muslim families will no longer have to choose between honoring the most sacred days on their calendar or attending school," Mayor Bill de Blasio said in his announcement.

Muslim leaders welcomed the announcement.

"After years of advocating by New York City's Muslim community, Muslim public school students will finally and thankfully no longer be penalized for observing their religious holidays," said Zead Ramadan, a board member of the Council on American-Islamic Relations.

Community leaders have urged adding the Muslim holidays to the school calendar. The City Council passed a resolution supporting the change in 2009.

The total number of school days will go unchanged in New York.

New York City public schools have long closed for major Jewish holidays such as Rosh Hashana and Yom Kippur as well as the Christian holidays of Christmas and Good Friday.

Other public school systems that have moved recently to observe Muslim holidays include those in Waterbury, Connecticut and Frederick County, Maryland.

The Associated Press contributed to this report