There was some party politics Wednesday night as the city’s top ballet dancers skipped their own bash as part of an industrial action campaign.

At the New York City Ballet’s glamorous Fall Gala held at Lincoln Center, dancers and stage managers staged a boycott protesting pay disputes with company management.

While celebrities such as Sarah Jessica Parker (serving as vice chair of the NYCB’s board), along with Julia Fox, Nicole Ari Parker, and Helena Christensen showcased on the red carpet, tension simmered behind the scenes. The performers had decided to forgo both the red carpet event and the extravagant post-performance party.

A mere thirty minutes before guests started to arrive at the David H. Koch Center, members of the American Guild of Musical Artists union, which supports the dancers, declared their action en releve in a message to the leadership. They expressed their inability to celebrate while their needs remained unmet.

The group says its just asking for a fair barre-gain, noting “NYC’s skyrocketing cost of living.” 

“[Management’s] proposed percentage increases fall far short of what AGMA Artists at nearly any other dance company nationwide have secured over the past twelve months, despite most of those companies operating without the financial stability that NYCB enjoys,” the group wrote in a letter.

Organizers seemed flat-footed over the protest, said sources.

The dancers performed at the gala, per their contract.

But afterward, guests including Amy Sedaris, Republic Records founder Monte Lipman and wife Angela, socialite Jean Shafiroff, and Bloomingdale’s executive’s Kevin Harter and Kelley Carter headed to a dinner — and found empty seats where there should have been the country’s top dancers.

One source tells us “by the time the dinner started the seats had been rearranged to not have the [dancers] places there.” But a second source said, “They may have scrambled to fix some, but the [place cards] in my section were still there.”

The union members have been working toward a deal since May with their current contract expiring in August.

There was an hours-long bargaining session just days before the gala event, but the union says management failed “to address the steep and ongoing cost-of-living increases in New York City.”

We hear there was no mention of the boycott during speeches at last night’s gala. The dancers and musicians did, however, receive a “special thank you” from Board of Directors Chair, Diana Taylor.

The AGMA/NYCB negotiating committee tells Page Six, “We fulfilled our contracted performances at the gala because we remain committed to our art and to our audiences. We also understand that the gala is a special evening for our benefactors and supporters.”

But, they said, they “made the collective decision not to attend the dinner or walk the red carpet because we wanted our absence to be felt.”

“We hoped to demonstrate, respectfully but unmistakably, how essential the artists are to this company,” they added,”It felt inappropriate to celebrate while our fundamental needs remain unmet. Our focus right now is on winning the fair contract we no doubt deserve.”

The NYCB told Page Six in a statement, “Yes, the dancers chose not to walk the red carpet or attend the dinner, but the show and post-performance dinner, with more than 800 guests in attendance, went on as planned.  NYCB management looks forward to returning to the bargaining table and reaching a mutually beneficial agreement for all involved. “

The Musicians of New York City Ballet, members of Local 802 AFM, have also weighed in, saying they are standing “united in solidarity with our incredible dancers and stage managers as they continue their contract negotiations. We know all too well how challenging it is to make a living and support a family as artists in New York City. What our dancers are asking for is both reasonable and fair.”