UPDATED 06/01/12 6:00 p.m.

CHICAGO (CBS)–The Chicago Teachers Union says it will conduct a strike authorization vote next week.

“We are tired of being bullied, belittled and betrayed by the district and by the city of Chicago. Enough is enough,” CTU president Karen Lewis said at a news conference Friday.

The vote will be taken Wednesday. A strike authorization vote would not necessarily mean there will be a strike. It would empower the union negotiating committee to call a strike if and when it so chooses.

But relations between the CTU and Chicago Public Schools – and City Hall – have been poor as Mayor Emanuel has aggressively pursued a longer school day over the objections of union officials who have advised more caution in implementing the plan.

CPS chief Jean-Claude Brizard said the June 6 strike-authorization vote is premature because it comes before the latest contract proposal is expected to be unveiled in mid-July.

“Teachers deserve a raise for the great work they are doing, and they also deserve an opportunity to see the proposal being put on the table before asking them to authorize a strike,” Brizard said in a written statement.

LISTEN: WBBM Newsradio Political Editor Craig Dellimore reports

Seventy-five percent of union members must vote “yes” in order to authorize a work stoppage.

Lewis says no teacher wants a strike, but if teachers “have to do this to get the resources they need for their students, they will.”

Last week, thousands of teachers and their supporters rallied and marched downtown demanding a new contract they can accept.

The union has accused Emanuel, Brizard and the Chicago Board of Education of leaving teachers out of efforts to improve schools and forcing them to accept a longer school day and longer school year without explaining how to pay for it or use the extra time to benefit students.

When talk of a strike began mounting earlier this month, the mayor said it was a distraction from the teachers’ real job.

“Anytime anybody’s not focused on their first priority – which is teaching our children – that’s where I get angst,” Emanuel said “There will be plenty of time for other discussions. Don’t take away from your main mission, your job, what the people of the city of Chicago, the parents, the taxpayers expect of you, which is to teach our children.”

Brizard said earlier this month that talk of a strike at this point is unfortunate.

“We shouldn’t be talking about the s-word. Let’s talk about finding a way to work together to improve a system that will benefit nearly a half million children,” Brizard said.

Brizard believes a major reason the union wants a strike vote now rather than in August is because the nearly 1,500 teachers who are retiring and who might be more likely to vote in favor of a strike, would not be eligible to vote in August.

Brizard doesn’t believe people who won’t be affected by the next contract–the retiring teachers–should not vote, that their replacements should.

The school system has proposed a 2 percent raise for teachers during the first year of the next contract. The teachers union reportedly has proposed a 24 percent raise. Brizard says, perhaps the number that’ll be agreed on will be somewhere in between, that those numbers may be “beginning places.”

Chicago teachers have not gone on strike since 1987. Back then, the teachers only needed a simple majority to authorize a strike.