28 LibertyTony McAteer

Four Seasons restaurateurs Alex von Bidder and Julian Niccolini, who are getting booted from the Seagram Building next July, have their eyes on a new, sky-high venue.

They’re quietly negotiating to take over the top of 28 Liberty, the reincarnated former One Chase Manhattan Building in the heart of downtown, The Post has learned.

The Chinese owners of the tower are in the midst of negotiating not just with the world-renowned Four Seasons, but with three other “household names” to run the restaurant, events and conference center in the magnificent former Chase conference center on the 60th floor of that building, sources said Friday.

Seagram Building owner Aby Rosen declined to renew The Four Seasons lease, and after Niccolini and von Bidder leave, the iconic space will be run by the Major Food Group team of Mario Carbone, Rich Torrisi and business partner Jeff Zalanick.

The Seagram venue will no longer be called The Four Seasons, because Niccolini and von Bidder own the name.

Developed for David Rockefeller’s bank in 1961, the 2.2 million square-foot 28 Liberty tower is bounded by Nassau, Liberty, William and Pine streets and is just one block north of the New York Stock Exchange.

The owner, the Fosun Group, a unit of one of China’s largest conglomerates, is determined to make this tower its flagship and launching pad for US investments.

It has also hired JLL to lease the 1 million square feet that Chase has left vacant.

“This asset is important for Fosun and important to brand themselves to the US business community,” said one source who was not authorized to speak.

To put its best face forward to the business community, on top of paying $725 million at the end of 2013 Fosun is also investing some $150 million into upgrades both outside (by reworking its barren plaza with lush plantings and world-class retail) and inside (with a new lobby, elevators, mechanicals and other tweaks) all the way up to this topmost floor.

“It’s a spectacular space,” explained another source, of the conference floors and its views.

Restaurateurs in the chase for this prize are also aware the space comes with a financial bonus that eludes other high-stakes operations: Since no unionized restaurant was here before, the next operators can also be union-free.

Representatives of the Four Seasons and Fosun declined comment.