Larry Silverstein looks to lure Amex to help him build final tower at Trade Center complex

Larry Silverstein is praying the third time’s the charm for Two World Trade Center.

The developer is in serious talks with American Express to anchor or completely fill the delayed skyscraper, which needs a tenant for Silverstein to get construction financing, according to a report.

The yet-to-be-built tower is the missing link in his otherwise successful commercial revival of the Trade Center site since the Sept. 11  terror attacks. Two earlier negotiations — with The Post’s owner News Corp and sister company Fox Corp., as well as with Citigroup — fell through after months of negotiations.

Amex has entered into an exclusive negotiating period with Silverstein, the Real Deal reported Thursday, and could make a decision whether to go ahead as early as this month.

Silverstein declined to comment.

One plugged-in industry insider told The Post, “It would be spectacular for Silverstein and the Trade Center, but it’s a helluva long shot. On top of astronomical costs, a relocation there would involve  a million moving parts, including the question of what Amex would do with its space at Brookfield Place.”

Amex owns one million square feet in the lower half of  200 Vesey St. Brookfield owns the upper half.

The credit card giant, which has said it intends to stay in Manhattan, could also consider other available downtown locations, such as more than one million square feet up for grabs at  Paramount Group’s repositioned 60 Wall St.

Amex could also entertain anchoring  one of several development sites in the Hudson Yards area, “but the World Trade Center has infinitely better transit options and access to the talent pools of Downtown,  Brooklyn and New Jersey,” a different source said.

Amex tapped Cushman & Wakefield two years ago to consider options, the Real Deal reported.

The proposed tower’s current design is by Norman Foster, whom Silverstein tapped to come up with a replacement for previous designs by Bjarke Ingels and by Foster himself earlier.

Silverstein had previously told The Post the design is “flexible” and can be changed to meet a tenant’s needs.

He also said construction requires no additional public approvals and could begin right away on the  site,  which is currently used for a beer garden.

“The foundation is built to grade. It’s ready to go,” he said.