Italian conductor Riccardo Muti, music director of the Chicago Symphony Orchestra, lent his star power in support of striking musicians on Tuesday. 

Muti had previously written a letter indicating his support for the musicians, who balked at management's pay and pension offers and went on strike after 11 months of labor negotiations failed to result in an agreement.

The labor dispute has raised questions about the future of one of the world's most venerated orchestras amid general concern in the classical music world over the sustainability of many institutions. 

"This is a moment of crisis," Muti told reporters in front of Chicago's Symphony Center, which was shuttered as dozens of musicians picketed outside. "The entire world - the musical world - is listening to what happens in Chicago." 

The key sticking point is pensions: the orchestra association wants musicians to transition from traditional pension plans to retirement savings accounts similar to those widely used in the private sector. 

The orchestra's association said it pays some of the highest salaries in the industry - 187,000 U.S. dollars on average. 

But musicians insist that losing traditional pensions, in addition to salaries not staying competitive with that of other major orchestras, will make it difficult to attract and retain top talent.

Muti, who said he was not opposing management but rather hoping to find common ground, emphasized that management had a "responsibility" to preserve the orchestra's stature.

The two sides were not scheduled to meet again until Friday. 

The strike follows a similar action at Chicago's Lyric Opera - represented by the same union as the symphony members - in October, when members of the premier arts institution walked out over cost-cutting efforts they said would reduce quality on stage.

(Top Photo: Chicago Symphony Orchestra conductor Riccardo Muti (C) joins striking members of the Chicago Symphony Orchestra as they picket outside Symphony Center in Chicago, March 12, 2019. /VCG Photo)