MUSIC

The New York City Opera has announced that its new production of Arnold Schoenberg’s “Moses und Aron” at Lincoln Center scheduled for Sept. 16 has been indefinitely postponed. The American Federation of Musicians Local 802 and the American Guild of Musical Artists, whose contracts with NYCO expired May 30, refused to give assurances that even if orchestra and choral rehearsals went forward the premiere would take place. Martin J. Oppenheimer, vice president of the NYCO board and the chief negotiator with the unions, said there is “no strike threat” and that “negotiations were proceeding in a non-crisis atmosphere.” NYCO’s “Don Giovanni” opened two weeks ago and other summer productions are scheduled to open as announced. Both sides say that despite the complexity of the new work, “Moses und Aron” can still be rescheduled once a contract is signed.