Officials with Portland Public Schools have declared an impasse in contract negotiations with teachers.
The Oregonian newspaper reports (http://is.gd/AvAQPX ) the announcement was made Wednesday morning at district headquarters.
Under state law, both sides must release their final offers within a week, followed by a 30-day cooling off period. A walkout wouldn't occur until late December at the earliest.
With nearly 50,000 students, the Portland district is Oregon's largest.
The teachers union last authorized a strike in 2003, but a deal was quickly reached.