The largest school district in the country is delaying the restart of in-person learning amid mounting pressure from the country’s largest teachers union.

New York City Mayor Bill de Blasio (D) announced on Tuesday that in-person schooling will be delayed for 1.1 million children across the city by 11 days to September 21. Parents will have the option for online or in-person once school begins.

"We are dealing with all unknowns, but the good unknown is when there will be a vaccine,” de Blasio said in a press conference on Tuesday. “Once we do we can start going back to normal.”

The decision comes on the back of concerns raised by parents and the United Federation of Teachers (UFT), the country’s largest teachers union, over whether proper measures were put in place to ensure health and safety.

There was also talk of a possible strike if the UFT could not reach a deal with the city over reopening safely. A strike would have been momentous as that hasn’t happened in the city since 1975.

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"There's no longer a disagreement on what schools need to have,” UFT President Michael Mulgrew said during the press conference, referring to the discussions that took place last week between teachers, administrators, and officials.

NYC stood out in its decision to reopen since Los Angeles and Chicago, the second- and third-largest school districts in the country, respectively, opted for remote learning. (As of Monday, there were 1,668 new cases of COVID-19 in Chicago. Los Angeles reported 1,030 new cases of COVID-19 on Sunday. New York reported 754 new cases on Tuesday.)

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The situation underscores how tricky the reopening process is, given the number of stakeholders involved.

Aside from the teachers who are concerned about their health and well-being, parents are also reluctant to restart in-person learning: A recent report by YouGov and SafetyCulture of 1,164 American parents found that only 43% of parents sending their children back to school are comfortable with their decision.

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