martinedoucet/iStock(CHICAGO) — The mayor of Chicago is asking for the city’s teachers union to stop the strike while continuing negotiations.

This comes as the strike in the country’s third-largest school district enters its fifth day.

Disagreements over pay, benefits and class size are among the top concerns that prompted the strike, which started on Thursday, Oct. 17. Monday marks the third day of school missed as a result of the strike.

Mayor Lori Lightfoot wrote a letter Monday to Chicago Teachers Union president Jesse Sharkey, calling for the teachers to return to the classrooms while negotiations carry on.

“While we have made progress at the bargaining table, it is unclear that we can reach an agreement today given the current pace,” Lightfoot wrote in the letter.

“The students and families of Chicago cannot afford to be out of school for any longer, which is why we are asking you to end the strike and encourage your members to return to work while bargaining continues. As someone who is concerned about the success of our students, we hope you see how necessary it is to reopen schools at this time,” Lightfoot wrote.

Lightfoot went on to give specific examples of the impact the strike will have on students, from a canceled college fair to the prospect of a prestigious football team being ineligible for the state playoffs, if the strike isn’t resolved by Tuesday.

For its part, the Chicago Teachers Union posted various videos of multiple strikes happening across the city Monday.

The CTU did not immediately respond to ABC News’ request for comment about Lightfoot’s letter, but there is slated to be an update on the negotiations Monday afternoon.

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