A charter school advocacy group on Thursday charged the de Blasio Administration with systematically denying  charter schools space in public school buildings since taking office in 2014, citing an internal report that indicated that the city denied 79 percent of such requests.

This happened despite passage by the State Legislature in 2014 of a law ensuring that charters have fair access to space, supporters alleged at press conference staged on the steps of City Hall.

‘We had to hold a meeting with families to tell them we might not have a school for their kids,” said Ian Rowe, CEO of the Public Preparatory Network who added that his organization was denied space repeatedly by the de Blasio administration after being approved for a co-location by the Bloomberg administration. He further charged that after Public Prep won their New York State Education Department appeal and secured private space, they almost lost their lease when the Department of Education contested the state’s decision.

Mayoral spokeswoman Freddi Goldstein strongly denied the claims.

“This analysis is deeply flawed and fails to take into account the whole picture,” she said.”Each request for space is individually assessed based on a variety of factors including building layout, type of space, ability to provide a contiguous school environment, and the needs of the greater school community. We work with charter schools as best we can to ensure high-quality school options, including co-habitation in public school buildings wherever appropriate.”

Petra Milteer has a kindergartener and a second grader in South Bronx Classical 3 Charter School. she said her boys are proud they can do addition.

“Learning gives children confidence” she said.

Charter school supporters also charged that South Bronx Classical Charter School was forced to cut down their enrollment to fit the available space. Instead

of a planned 90 seats in their most recent lottery, they could only admit 30 new students.