(CBS) – Chicago Public Schools officials are backing off a threat to make teachers pay a portion of their pension, but it might not be enough to halt a work stoppage early next month.

CBS 2’s Dorothy Tucker reports on the latest back-and-forth between the Board of Education and teachers, a day after CPS announced all employees would be required to take three unpaid furlough days before the end of the current school year.

Teachers are still promising some kind of work action on April 1. Union representatives say they’re still working out the details.

“April First would be an unfair labor practice ‘day of action.’ It’s a showdown,” CTU President Karen Lewis said.

The idea of a strike was still a possibility, despite CPS CEO Forest Claypool’s announcement he will not force the teachers to contribute to their pensions – not now, anyway.

“We have a clear and unequivocal right under the contract to no longer pay the 7 percent of the 9 percent teacher contribution,” Claypool said, “but we want to negotiate to try to come to a global agreement.”

He says teachers could not walk off the job until mid-May, at the earliest.

The CTU disagrees.

“The United States Supreme Court ruled 60 years ago that a strike over unfair labor practices is different from a strike over a contract,” said Robert Bloch, attorney for the CTU. “It does not need to follow the notice and timing requirements under the statute. It’s free to act on its own, and the union reserves the right to do that.”

CPS officials say they’ll take the teachers to court if they strike.

Dorothy Tucker