CHICAGO (AP) — Chicago Mayor Lori Lightfoot demanded Thursday that the city’s teacher’s union reach an agreement on COVID-19 safety protocols by the end of the day and bring students back to the classroom, but did not say what she would do if that doesn’t happen.

Speaking during a news conference, Lightfoot was visibly angry at the Chicago Teachers Union for giving her the runaround, saying that her office and the school district officials have not received a straight answer on the union’s demands.

“We waited for hours and hours last night and still did not receive a proposal from the CTU leadership, and as of this morning we are still waiting,” she said. “We need to get a deal done and get it done today. I expect to hear from them, no more delay.”

But the threat was only implied; Lightfoot declined to say what she would do if no deal was reached by day’s end.

Part of the reason, is perhaps, that students do not have class Friday. That means the union and the city could continue to negotiate through the weekend. But Lightfoot made it clear she is not interested in any Sunday night negotiations, telling reporters that she has no plan to be standing in front of a podium talking about negotiations.

“If you’re going to be here, you’re going to be by yourself,” she said.

Lightfoot said one thing the city is not going to do is sue the school district, as was done this week in San Francisco for the simple reason that while the mayor of San Francisco doesn’t have any authority over the school district, in Chicago she does.

Lightfoot reiterated what she has been saying for days: It is safe for children and teachers to return to schools after Chicago Public Schools spent roughly $100 million on its safety plan, including purchasing air purifiers, deep cleaning schools and offering COVID-19 testing for teachers.

But the union, which last went on strike in 2019, says infections continue and the safest option is online learning. They also argue few students are interested in returning. Less than 20% of pre-K and special education students eligible to return to class last month, or about 3,200 of 17,000, attended.

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