The union representing New York City Opera's chorus assumes it will be locked out by the troubled company if a labor agreement isn't reached by the scheduled start of rehearsals on Monday.

Alan Gordon, national executive director of the American Guild of Musical Artists, said Friday that it's possible a deal could be reached that would avoid a work stoppage but that the unions could decide to end talks Saturday.

AGMA, the orchestra union and the company have been meeting with a federal mediator. The city opera announced in May that it was leaving Lincoln Center for the Performing Arts, its home since 1966, to perform at several venues. Its first opera of the season, Verdi's "La Traviata," is scheduled to open at the Brooklyn Academy of Music on Feb. 12.

AGMA and Local 802 of the American Federation of Musicians, which represents the orchestra, have been without a contract since the spring.

"NYCO has indicated to the mediator that it has more money to offer in severance pay and more health insurance for both choristers who continue to work and those who would rather sever their ties with City Opera," Gordon said.

"Assuming that this turns out to be true, and assuming that NYCO can likewise meaningfully address the other key AGMA and the key 802 issues, it's conceivable that a tentative deal could be reached," he added. "Given NYCO's history, there's no compelling reason to believe that it will actually come to pass. If no deal is apparent by 6 p.m., the unions will stop negotiating and, I assume, that NYCO will lock out AGMA members on Monday."

New York City Opera spokeswoman Risa Heller declined to respond to Gordon's comments.

"We are meeting to work on reaching a deal and will continue to respect the requested press blackout," she said.