The development of a New York City skyscraper that will house Ken Griffin's Citadel is moving forward despite Griffin's feud with New York City Mayor Zohran Mamdani.

The project at 350 Park Avenue is being developed by Griffin's Citadel in partnership with Vornado Realty Trust and Rudin, and two of Griffin's firms will serve as anchor tenants. With demolition now underway at the site, the project remains one of the more closely watched commercial developments in Midtown, where large new office towers often depend on long planning timelines, major capital commitments and tenant pre-leasing before construction can move ahead.

Steven Roth, CEO of Vornado Realty Trust, said during the company's earnings call on Tuesday that the project is underway and that the real estate investment trust plans to maximize its stake in the venture.

"If you drive or walk past Park Avenue at 52nd Street, you will see that our 350 Park Avenue site is now under construction, actually under demolition. We intend to shortly exercise our investment option to participate in this deal at our maximum ownership alongside Ken Griffin as our 60% partner and with Citadel as our 1-million-square-foot anchor tenant."

Roth said Citadel holds a 60% stake in the partnership, while Vornado's stake will top out at 36%.

The project has advanced after Mamdani specifically criticized Griffin for owning a penthouse on Central Park South in a video about his new pied-à-terre tax, which is levied on high-value residential properties whose owners do not live in the city full time.

Mamdani sparked the controversy with an April 15 video recorded in front of Griffin's penthouse, where he singled out the hedge fund billionaire as someone who would be subject to the new luxury property tax.

"When I ran for mayor, I said I was going to tax the rich. Well, today we're taxing the rich… This is an annual fee on luxury properties worth more than $5 million whose owners do not live full-time in the city – like this penthouse, which hedge fund CEO Ken Griffin bought for $238 million," Mamdani said in the video.

Griffin responded by calling the personal attack "creepy and weird," saying it put him in harm's way and reflected a "profound lack of judgment" on Mamdani's part.

Citadel executives later suggested that the new office space could become a casualty of Mamdani's business policies.

Gerald Beeson, the firm's COO, wrote in an April 23 memo to employees that development of 350 Park Avenue was about to begin and would create "6,000 highly paid construction jobs" and support the "creation of more than 15,000 permanent jobs in Midtown New York."

"The project – if we move forward – will entail more than $6 billion dollars of spending," Beeson wrote.

Mamdani eventually softened his rhetoric and thanked Griffin for his contributions to the city, including funding a memorial wall for police officers killed in the September 11 attacks and those who died of illnesses related to the recovery from the attacks. The memorial is set to open later this year at NYC Police Headquarters.

FOX Business' Robert McGreevey contributed to this report.