Advocates for school integration are urging Mayor de Blasio to use his final 100 days in office to push through long-debated reforms to reduce racial segregation in city schools — including eliminating separate “Gifted and Talented” classes and altering admissions rules for middle and high schools.

“New York City continues to be one of the most segregated metropolitan areas in the country,” wrote the Integration Coalition — a group of nonprofits including the NYU Metro Center and Teens Take Charge — in a Thursday letter.

“There is no justification for carrying on this legacy, particularly after a global pandemic that laid bare the deep disparities and deadly consequences of segregation,” the letter continued.

De Blasio has long touted his commitment to reducing racial segregation in the city’s divided public school system, but has been slow to enact citywide reforms — waiting until the COVID-19 pandemic upended the school system to make sweeping changes to the city’s notoriously complex school admissions system.

Last winter, De Blasio temporarily barred city middle schools from using grades, test scores and attendance records to decide who gets admitted — a change that’s already boosted the diversity at some sought-after middle schools. He also permanently scrapped a geographic preference for high school students in Manhattan.