New York City Mayor Bill de Blasio held firm Thursday to plans to reopen the nation’s largest public school system within a month, despite pleas from teachers and principals to delay the return of students to classrooms.

The city is aiming for a hybrid reopening Sept. 10, with most of the 1.1 million students spending two or three days a week in physical classrooms and learning remotely the rest of the time. Parents were given the option of requesting full-time remote learning for their children.

The Democratic mayor conceded there were challenges with the plan as the city recovers from a pandemic. But he said the city has managed to lower the rate of positive cases to around 1% and that it owes it to children and their families to reopen promptly.

“Our kids need to be in school,” de Blasio told reporters during a briefing. “Our parents are very, very concerned that our kids have already lost a lot of their education, that they’ve gone through a lot of trauma. We’ve got to get them back into school buildings where they can get so much more support.”

Many of the nation’s other largest school districts plan to start instruction online this fall.

The comments came a day after a union representing school administrators sent a letter to de Blasio and Chancellor Richard Carranza saying school leaders still had questions on issues ranging from staffing, to personal protective equipment, to ventilation system repairs.

“Regrettably, the city started the planning process far too late for them to have any faith or confidence that they can reopen their buildings on September 10th,” according to the letter from Council of School Supervisors and Administrators President Mark Cannizzaro.

The United Federation of Teachers has raised similar concerns, with union president Michael Mulgrew asking Wednesday whether any parent would be willing to send their children to a school where the principal believes the building is not ready to open.

De Blasio, who announced there would be a nurse in every school building, said there’s still a month to address concerns.

(AP)