A New Jersey club named after explorer Amerigo Vespucci is crashing America’s 250th birthday party aboard a namesake Italian tall ship — thanks to a former G-man.

When Amerigo Vespucci Society board member Joe Valentino found out the breathtaking Italian naval vessel was sailing into New York Harbor as one of the 48 tall ships in the Sail4th 250 celebration, he scrambled to get his club aboard the 331-foot giant before its return to Italy.

With efforts starting to sink, Valentino hit up his longtime pal, ex-FBI Director Louis Freeh, who has a summer home in swanky Spring Lake and frequently visits Valentino’s popular eatery there, Joe’s Deli.

Freeh, who ran the FBI under ex-President Bill Clinton, said he’d make a few calls, and ultimately got Joe Guccione, a former US Marshal for the Southern District of New York and board member of the National Italian American Association, to help.

Guccione reached out to the Consulate General of Italy and it was smooth sailing from there, according to members of the Long Branch-based Amerigo Vespucci Society.

Pasquale Perrotta, the Italian Navy’s attaché to the United States and Canada, sent a June 4 email shared with The Post to Roberto Ferragina, a past president of Amerigo Vespucci Society and current board member, confirming a visit for 30 guests aboard the 96-year-old ship on July 6 while it’s docked on Pier 86 in Hell’s Kitchen.

“This might be the biggest moment ever in the 151-year history of our club,” said Valentino, 74. “We are all ecstatic.”

Valentino said he got the idea six months ago watching a TV news segment mentioning the iconic “Amerigo Vespucci” vessel was returning to the US for the 250^th anniversary festivities — the same way it famously crossed the Atlantic in 1976 to participate in “Operation Sail” for the Bicentennial celebration.

“I contacted and pressed every button I could to make this happen,” recalled Valentino, who asked Freeh for help while the ex-FBI director was eating at Joe’s Deli.

The vessel will host Valentino, Perrotta and 14 other members of the group – which is the oldest Italian American mutual-aid society in the US — for an exclusive tour and small ceremony.

Other attendees will include Long Branch Mayor John Pallone, who will present the crew a proclamation from the city; members of the New Jersey Italian Heritage Commission, who also lobbied for the meet-and-greet; and Monmouth County officials.

Perrotta said his club will present the vessel’s crew with a plaque reading “From one Amerigo Vespucci to another – with pride gratitude and admiration. Though separated by ocean, we are united by a common name, a shared heritage, and an enduring commitment to the values of Italy.”

“This is a once-in-a-lifetime opportunity for us to embrace part of our history, and I’m humbled,” Perrotta told The Post.

The Italian explorer is credited as the first to recognize the Americas as a separate continent. These new landmasses were named “America” when the first world map was published in 1507 using a Latinized version of Vespucci’s first name.

Freeh could also attend the ship meetup if his schedule allows, said Valentino.

Freeh’s mother was an Italian-American, and the ex-FBI director holds dual US and Italian citizenship.

However, Freeh can’t join the Amerigo Vespucci Society because its strict bylaws require members to have Italian last names.

“He would love to, but he can’t because we are old school,” said Valentino.