The developers behind the controversial affordable housing project slated for the site of the Elizabeth Street Garden in Nolita sued Mayor Eric Adams on Wednesday, arguing he overstepped his powers by declaring the lot city parkland in order to kill the construction effort.

The group Haven Green has for years planned to build a 123-unit residential building for low-income seniors on the city-owned land, which is leased by the garden’s operators. The Adams administration previously planned to evict the garden to make way for the development, but changed course in June when officials said they cut a deal to eventually build other affordable housing elsewhere in the area.

Adams went a step further days after the general election by designating the lot as parkland, saying this would help prevent a future administration from building anything on the site.

The developers argued in the lawsuit that the mayor doesn’t have the authority to declare a property parkland by “fiat,” claiming the move was “an extraordinary act of executive overreach” aimed at killing “a duly approved, shovel-ready affordable housing development.”

The developers argued any new park must move through the city’s land-use process, which requires approval from the City Council.

“The Haven Green project is the product of an exhaustive public process and lawful governmental decision-making that has taken place for more than a decade,” the group said in a statement.

Mayor-elect Zohran Mamdani said during his campaign he would move forward with the garden’s eviction. But after Adams declared the site as parkland last week, Mamdani said it would be “nearly impossible” to build the housing project because major construction on parkland requires approval from the state Legislature.

Representatives for Adams did not respond to a request for comment Wednesday.

The group behind the Elizabeth Street Garden said they’re open to working with the incoming Mamdani administration to preserve the space, and added that Adams’ move to designate it as parkland reflects its “environmental, cultural and artistic significance.”

"Today’s lawsuit by the Haven Green development team is a misguided attempt to overturn a lawful and long-overdue action by the City of New York to protect one of the last remaining green spaces in our neighborhood,” the group said.

The yearslong debate over the garden has pitted housing advocates against Lower Manhattan residents who argue the garden should be preserved.

First Deputy Mayor Randy Mastro said in June that he made a deal to advance more than 600 units of affordable housing in areas near the garden. At the time, he said developers could break ground on one of the new developments by around the end of the year.