Bernie Ecclestone last week confirmed reports that the New Jersey street race will not be ready to host its inaugural race next season.
Promoter Leo Hindery jr said in a statement: "We are going to be racing at Port Imperial, unfortunately just not as soon as we hoped and expected."
He admitted the organisers need "additional time" to get ready for Formula One, for developing the facilities and garages.
"But we remain 100 per cent committed to the Grand Prix of America at Port Imperial, and the race could have no better partner and friend than the CEO of Formula One, Bernie Ecclestone.
"We benefit greatly from his experience and counsel, and from his support."