PROVIDENCE, R.I. (AP) — Providence public school teachers have voted to authorize work-to-rule if contract negotiations with the city scheduled for later this week do not lead to progress.

Providence Teachers Union President Maribeth Calabro said 1,940 members approved the measure Monday after two years without a new contract. Work-to-rule means that teachers only do what's contractually required.

Calabro stressed that the work-to-rule vote is "contingent on the success or failure of Thursday's session." She says she is "cautiously optimistic" that progress will be made. Students are scheduled to return to school Tuesday.

Calabro said Mayor Jorge Elorza had agreed to give teachers raises last winter and then reversed course. Elorza said raises are contingent on a "transformational contract that would improve outcomes in city schools."

An Elorza spokeswoman called the union's vote "disappointing."