First Deputy Mayor Lorraine Grillo is leaving Mayor Eric Adams’ administration, City Hall announced Friday — the third major departure from his leadership team in recent months.

Grillo is a government veteran with about 30 years of public service and was one of the mayor’s top lieutenants. She helped set up the Adams administration in its first year and was instrumental in projects like the development of the CUNY Brookdale Campus, the city’s COVID-19 response and overhauling the capital projects process.

“Public service has been my life’s work, and it has been the honor of a lifetime to serve in the Adams administration in this capacity,” Grillo said in a statement.

Rumors of the move were reported two months ago by The Daily News and confirmed Friday morning by Politico, ahead of the official announcement.

Grillo's exit follows the departure of Adams' chief of staff Frank Carone, as well as the recent resignation of Department of Buildings Commissioner Eric Ulrich amid allegations he was involved in an illegal gambling operation.

“New York City, as a whole, is better off today because Lorraine Grillo brought her invaluable expertise and inimitable work ethic to this administration and served the people of this great city,” Adams said in a statement.

Speaking to Fox 5, Grillo said Friday that she had initially told the mayor she only intended to serve one year. Her intention, she explained, was to “lay the groundwork to get the government moving.”

“We made that arrangement at the very beginning,” she later added.

Grillo hailed the administration for tackling the recent migrant crisis, describing a team of officials who were relatively new to city government and forced to navigate a challenging situation.

“These folks — who had no experience in this — jumped forward and got things done, and helped people along the way,” she said.

Minutes into the interview, Adams and his chief adviser Ingrid Lewis-Martin appeared to surprise Grillo on the set. Adams delivered a bouquet of flowers along with a bottle of champagne. But the mayor did not provide any hints about her replacement.

“You’re not going to get another Lorraine Grillo, plain and simple,” he said.

Grillo, an Astoria native, started out as a community relations specialist for the New York City School Construction Authority in 1994, according to the city. In 2010, she was appointed SCA president and CEO by former Mayor Michael Bloomberg. She went on to serve as pandemic “recovery czar” under former Mayor Bill de Blasio, before landing the role of first deputy mayor under Adams — one of the most senior leadership positions in City Hall.

She is expected to finish out the year in office and has not said what her next move will be.

This story has been updated with additional comment and information.