The concerts, which start later this month, would be music director-designate Kent Nagano's first since his appointment was announced last year.
The threat is apparently intended to jumpstart the negotiations, which have dragged on for more than a year, as well as to prevent a public protest by the musicians at the high-profile concerts. "It would be entirely unacceptable for Kent Nagano's collaboration with the [orchestra] to commence in a climate of protest and pressure tactics," a spokesperson said in a statement. In the past, musicians have worn red union t-shirts and skipped rehearsals in protest of management's position.
Musicians have been playing without a contract since August 2003; according to management, the two sides have met 39 times without significant progress. Management has sought to reduce costs by changing work rules surrounding concerts, tours, and recordings.
The programs for the concerts in question, scheduled for March 30 and April 1, 5, and 6, include Mahler's Third Symphony and Messiaen's ê_clairs sur l'au-del_.