The Chicago Teachers Union’s bargaining team has rejected a contract proposal from Chicago Public Schools, citing the district’s financial woes and an overall lack of trust. 

Teachers union president Karen Lewis said the 40-member team went through every single article line by line and unanimously voted down the proposal midday Monday. 

“What we are looking for is sustainable funding…which means serious revenue,” Lewis said. “That is not in this contract. There’s no guarantee that the promises that are made are promises that can be kept.”

The exact details were not made public, but CPS officials said the deal included teachers raises for seniority and experience and a commitment to slow charter school expansion and give teachers more “classroom autonomy.” But it also included a phase out of the pension pick-up and increases in health care premiums. 

In a statement, CPS CEO Forrest Claypool said he was disappointed in the decision, but remains committed to reaching an agreement.    

The two sides now begin a formal mediation process known as fact-finding that by law could take 75 days. The soonest teachers could walk off the job would be May 23.

But the two sides have agreed to keep bargaining. A spokeswoman for the union confirmed that negotiations continued Tuesday morning. 

The rejection of a possible deal comes at a time of instability in CPS. 

At the start of the school year, Claypool proposed a deficit budget — that the Board ultimately approved — that left a gaping $480 million gap between projected revenues and projected expenses. Initially, Claypool sought revenue from state lawmakers to avoid what he said would be massive budget cuts in the middle of the school year. 

The district continued to ask Springfield for help through the fall, until it became very clear that it wasn’t going to happen. Last month, Gov. Bruce Rauner and republican leaders proposed a state takeover of CPS and a path to bankruptcy for the district.

With the second semester starting on Feb. 8, CPS officials have been frantically working to close this year’s deficit by getting a contract signed with the Chicago Teachers Union and borrowing money through bond markets. 

Last week, the district delayed a bond sale worth $875 million. The next day Moody’s downgraded CPS’s bond rating further into junk status.

Becky Vevea is an education reporter for WBEZ. You can follow her @WBEZeducation.