LENOX, Mass. (AP) — The union for Boston Symphony Orchestra musicians authorized the first strike in the ensemble’s 145-year history on Saturday.

The Boston Musicians’ Association issued a statement ahead of the expiration of the union’s three-year contract at 11:59 p.m. Sunday.

The orchestra and management have had strained relations since BSO decided in March to force out music director Andris Nelsons next summer after 13 seasons.

“In spite of the turmoil of the last six months caused by BSO’s leadership decision to terminate the orchestra’s musical director, Andris Nelsons, they have failed to agree to a collective bargaining agreement that would begin to restore the trust that they have destroyed and offer a fair contract to the musicians who are at the heart and soul of the BSO,” the union said in a statement.

The union said management has not agreed to musicians’ proposal for a mediator.

“We respect the musicians’ right to take this step as part of the negotiating process,” BSO CEO Chad Smith said in a statement. “Our focus remains on the negotiations and the ongoing constructive conversations. We are committed to reaching an agreement with competitive pay and benefits that enhances collaboration with the players.”

The orchestra’s season is scheduled to open Sept. 17.

The Associated Press