La Scala canceled "Requiem," which was to have been performed Saturday in the opera city of Parma as part of commemorations marking the 50th anniversary of Arturo Toscanini's death. It also canceled Saturday's performance of "Cosi fan tutte" in Milan.
A Nov. 9 performance of "Requiem" at La Scala also was canceled due to the labor dispute, but other performances have gone on as scheduled in the interim, including a gala concert conducted by Daniele Gatti on Tuesday night.
The continuing labor tensions are casting a shadow over the Dec. 7 season premiere, this year featuring Wagner's "Tristan und Isolde.
The premier, which opens the opera house's 2007-08 season, is the social and cultural event of the year in Milan society. It has never been canceled by a strike, as far as officials can remember.
La Scala's employees - including the orchestra and choir - say they have not had a pay raise in seven years, but the management of the opera house say they cannot negotiate with its employees unless nationwide contract talks are ongoing in the sector.
Just three days ago, national union officials submitted their position, which is the first step toward opening national talks, La Scala spokesman Carlo Maria Cella said. No timetable, however, has been set.
Following last week's strike, La Scala general manager Stephane Lissner pressed the issue with Culture Minister Francesco Rutelli on the sidelines of an event honoring the late Luciano Pavarotti.