The Chicago Teachers Union is considering a "serious offer" made by Chicago Public Schools officials, according to a statement released by the labor group Thursday evening.

"After a period of intense and difficult bargaining, the CTU has received a serious offer from Chicago Public Schools. The CTU requires that any Tentative Agreements be made by its Big Bargaining Team, a 40 member committee of teachers, PSRP's and clinicians, which will convene, deliberate, and vote on Monday. While the Union will not release details of the offer without Big Bargaining Team approval, the basic framework calls for economic concessions in exchange for enforceable protections of education quality and job security. If the Union is able to reach a Tentative Agreement, delegates will be apprised of details shortly," said CTU President Karen Lewis.

The Chicago teachers' contract expired in June of 2015. Union members voted to authorize a strike last month. 

Check back with Progress Illinois for more on this developing story.

UPDATE (6:35 p.m.): CPS CEO Forrest Claypool released the following statement about contract talks with the CTU:

As the CTU leadership said, CPS has put a serious offer on the table that would prevent midyear teacher layoffs. This offer is a true compromise that requires sacrifices from both sides so that we can protect what is most important: the gains our students are making in their classrooms. We will continue to work around the clock to reach consensus on an agreement that is the best interests of our students, educators and parents.