PORTLAND, Ore. — A 23-hour bargaining session has led to a conceptual agreement that could avert a first-ever teacher strike in Portland public schools, the biggest district in Oregon.

PORTLAND, Ore. — A 23-hour bargaining session has led to a conceptual agreement that could avert a first-ever teacher strike in Portland public schools, the biggest district in Oregon.

Bargainers took a break Tuesday morning and are set to come back later in the day to iron out details and put the agreement in writing.

Becca Uherbelau (UR'-behl-ow), a spokeswoman for the teachers union, says plans for strike that had been set to start on Thursday will go on hold once that happens, pending ratification of a contract by teachers and the school board.

Uherbelau says details of the agreement won't be released until teachers hold a contract vote.

The district has 48,000 students and 2,900 teachers.