NEW YORK (Reuters) - The family-owned company that until recently was headed by U.S. President Donald Trump’s son-in-law hopes to turn an aging New York office tower into a signature development that could be worth up to $12 billion, a report said on Wednesday.

FILE PHOTO - Passers-by walk near the office building at 666 Fifth Avenue in New York December 7, 2006. REUTERS/Keith Bedford

Chinese insurer Anbang Insurance Group is in advanced talks to provide as much as half of $2.5 billion in equity for the planned redevelopment of 666 Fifth Avenue, the Wall Street Journal reported.

The overall project for the flagship 39-story building, which is controlled by Kushner Cos, is valued at $7.5 billion. The company was run by Jared Kushner, who is married to Trump’s daughter Ivanka. He sold his stake to a family trust in January.

Extensive talks are under way between Kushner Cos., its partners in the building, potential investors, lenders and tenants who would have to be paid to move for the project to go forward, the Journal said, citing people close to the deal.

Plans call for stripping the structure down to its steel columns and adding about 40 floors to the building, which was built in 1957. The project was designed by Zaha Hadid, a Pritzker Prize award winner for architecture, before she died last year.

Concerns about a conflict of interest given Jared Kushner’s role as an advisor to Trump could halt Anbang from taking part. Anbang last week said it was not investing in the project after Bloomberg News named the firm as a potential investor.

Kushner Cos believes it could gain the necessary equity from other investors if Anbang decides to exit the transaction, the Journal said. The project faces other hurdles.

The Kushners would have to buy out the building’s current tenants to allow for domolition to start and an existing $1.15 billion in debt would need to be refinanced.

Talks are under way with Vornado Realty Trust, a real estate investment trust that owns 49.5 percent of the building’s office space and much of the property’s retail space, to buy out its interests, the Journal said.

The need to sell the luxury condo units at near record prices and the overall financing for the project could raise the eyes of the U.S regulators, a banking source said.