Making good on its threat, the new leadership of the Philly Pops filed a motion Monday in U.S. Bankruptcy Court seeking to end the organization's relationship with Peter Nero, its music director of 33 years.

Nero's contract, the Pops said in its filing, is "simply too economically burdensome." The Pops "can no longer afford to compensate Nero at the levels provided for in the employment agreement while simultaneously hoping to continue its existence in the future."

The Pops has begun the search for a replacement for Nero for the 2012-13 season - even as tickets have already been sold for concerts billed as being led by Nero - and will import guest conductors for lower fees, the filing states. The motion requests an expedited hearing in court, with a rejection of the contract by June 30.

Nero is fighting the move.

"We don't think it's Peter that needs to go, but the board that needs to go," said Nero's lawyer, Albert A. Ciardi 3d. Ciardi said he had only briefly looked at the motion, but was preparing a strategy that would keep "Nero performing with the Pops. We don't believe they have a very good business justification for doing this.

"Peter is the Pops, and the Pops is Peter."

If successful, the rejection would end an institutional personification that has been Philadelphia's answer to other rarefied pops partnerships such as Arthur Fiedler's Boston Pops and Erich Kunzel's Cincinnati Pops Orchestra. Nero has characterized the move as a "takeover attempt" of the ensemble he has led since its founding in 1979 by impresario Moe Septee.

The move to oust Nero, 78, comes after an unsuccessful attempt to renegotiate his contract in the middle of its term. The Pops has sought to impose a 40 percent pay cut on Nero, whose most recent annual compensation was $513,000, according to Frank Giordano, the Pops' president and chief executive. Nero has disputed that figure, saying it included office space, storage, transportation, and other expenses related to his job as both conductor and the artistic chief.

The effort is being led by Giordano, who started as a volunteer before beginning to pay himself a $1,000-per-week salary in January.

Board chairman D. Walter Cohen last week called the rejection of Nero's contract "very disturbing." Giordano said the June 5 board vote in favor of the move was "almost unanimous," but, in fact, Cohen said, three board members voted against it - himself included - and one abstained. The size of the board has been increased by Giordano to 26 members with plans for 30, with Giordano's appointees lining up behind him, and the old guard voting against Nero's removal.

One solution, which Cohen said he argued for at the board meeting, would be delaying the hiring of a new chief operating officer to save money. Giordano has prepared a budget for next season that calls for hiring that additional administrator, plus raising his own salary to $91,000 a year. Cohen called that "a problem."

Cohen said he had urged a compromise between Nero's current compensation and the cut advocated by Giordano. He said he was afraid Nero's absence would hurt ticket sales.

"I think there are people who, as far as they are concerned, Peter is the Pops," he said.

The Pops has sold subscriptions for next season to 1,200 households, a spokeswoman said. TicketPhiladelphia agents have been given a sheet with talking points telling callers that the Pops and Nero were still in discussions, meant to dissuade concerned subscribers from asking for refunds.

The Pops was drawn into bankruptcy when its parent organization, the Philadelphia Orchestra Association, filed for Chapter 11 bankruptcy protection in April 2011. The two groups have since split. The Pops has taken the opportunity to renegotiate its contract with Nero, which was not set to expire until June 30, 2014.

The current pact calls for a minimum compensation of $360,000 per year plus other perks, though a chart in the court filings shows the amount paid to Nero as high as $750,000 in 2008. The conductor says that those totals include expenses associated with running the organization such as office space and transportation and that his personal compensation is much lower.

The Pops contends that Nero's compensation is so high relative to a sampling of other salaries at other pops orchestras that it represents "an anomaly in the classical music business."

The Pops says it is seeking an expedited hearing, in part so it has time to find a replacement conductor for the traditional Independence Day concert, scheduled this year on July 3 at Independence Hall. The concert is still on, a Pops spokeswoman said, but Nero may not be on the podium leading the orchestra.

"I'm not sure who it will be," the spokeswoman said.

Reached late Monday, Nero would not comment on the filing, but he said: "I am completely confident that I will be leading the Philly Pops in our 11th year in front of Independence Hall."

Contact Peter Dobrin at 215-854-5611,