Mayor-elect Zohran Mamdani has tapped a 74-year-old former high-ranking de Blasio administration official and longtime budget guru as his top City Hall advisor.

The appointment of Dean Fuleihan as first deputy mayor marks the first major staffing decision for the incoming Mamdani administration that wants to spend more than $10 billion on a lofty socialist agenda while facing down a nearly $5 billion budget gap.

Fuleihan, who is more than twice the age of the 34-year-old socialist lawmaker, also served as then-Mayor Bill de Blasio’s first deputy mayor and had been advising Mamdani on his campaign.

“I think that Dean is in a position to serve any mayoral administration,” said Emma Wolfe, ex-top advisor to de Blasio. “Given his background in fiscal and policy, I think he’ll be a valuable public official.”

The veteran city and state government official got his start in the late 1970s as then-State Assembly Speaker Sheldon Silver’s budget chief.

He was appointed as the city’s budget director in 2013 and lauded by de Blasio at the time as a “true progressive” following a more than three-decade run in Albany.

Over his four-year stint, New York City’s budget surged from $72 billion to $85 billion, with some members of the City Council ripping the administration for not saving enough to navigate cuts under a Trump presidency.

Fuleihan, 74, served as Bill de Blasio’s budget director from 2014-2018, before becoming first deputy mayor. David McGlynn

The septuagenarian public servant re-enters Big Apple politics at a similar time as both the city and state anxiously awaits the effects of the impending federal funding cuts that could severely hinder Mamdani’s $10 billion in campaign promises, in the form of free buses and universal child care.

Mamdani, 34, and his close advisors have faced criticism for their age and have been urged to bring on officials with more experience. REUTERS

Mamdani has the backing of Gov. Kathy Hochul when it comes to rolling out free child care, but the two have yet to figure out how the pick up the $6-$8 billion tab.

Hochul named Fuleihan New York State Financial Control Board in June 2024.

Fuleihan served under de Blasio for both terms. Paul Martinka

Also named to a top spot Monday was Elle Bisgaard-Church, who will unsurprisingly serve as the mayor’s top advisor. Bisgaard-Church has been with Mamdani for years and was the architect behind his insurgent campaign.

Insiders have been gossiping for weeks about who Mamdani would tap as his first deputy, with current planning commissioner, Dan Garodnick, and another de Blasio first deputy mayor, Anthony Shorris, topping the list.

Outgoing City Comptroller Brad Lander thought he had the role locked up after forming an alliance with Mamdani in the final days of the Democratic primary — boasting that he would be the influential adult in the room in City Hall, sources said.

But, according to sources, the Democratic Socialists of America member wasn’t too impressed with Lander, describing his schtick as the good government policy wonk as a mere act.