NEW YORK CITY — Citadel founder Ken Griffin said he would shift his business expansion focus to Miami rather than Manhattan following a public clash with New York City Councilman Zohran Mamdani over a proposed luxury property tax.

Griffin, the chief executive of the hedge fund Citadel, said Mamdani was "making it really clear: New York doesn't welcome success." He also said he would "double down" focusing on Miami to grow his business interests rather than Manhattan. Griffin owns the most expensive apartment in the United States, which he purchased in 2019 for $238 million.

The dispute followed an April video that Mamdani filmed outside Griffin's New York penthouse to promote a new tax on luxury properties in New York City. He called the video "creepy and weird" and warned that it posed security risks, citing the nearby fatal shooting of UnitedHealthcare chief executive Brian Thompson. "Anything that creates, like an agitation, in the extremist on either side of the aisle is a frightening dynamic," he said.

Mamdani has said a pied-à-terre tax on properties worth more than $5 million in New York City would raise at least $500 million annually. He has also said raising taxes on the wealthy could provide as much as $9 billion for his agenda and has proposed increasing the corporate tax rate from 7.25% to 11.5%. "When I ran for mayor, I said I was going to tax the rich. Well, today, we're taxing the rich," Mamdani said.

Press secretary Joe Calvello said the mayor wants all New Yorkers to succeed and praised the business owners and entrepreneurs who "make this city the economic engine of America." "That does not negate the fact, however, that our tax system is fundamentally broken," Calvello said. He said the status quo in New York is "unsustainable and unjust" and "rewards extreme wealth while working people are pushed to the brink."