(New York, NY -- Ilya Marritz, WNYC)  Senator Charles Schumer  (D-NY) warned on Friday that it will get more and more difficult to construct two Amtrak rail tunnels linking New Jersey and midtown Manhattan, unless the forces of government and the private sector quickly align.

"There is a major issue that has to be resolved right now or else the project may end up in the graveyard, as it did with ARC,"  Schumer said, referring to a previous rail tunnel plan that was killed by New Jersey Governor Chris Christie in 2010.

The reason? A new mixed-use neighborhood is being built on Manhattan's west side, on a platform directly above the site where the rail tunnels would emerge from below the Hudson.

"Amtrak's engineers have determined that the only place they can bring these new tunnels into Manhattan is under Hudson Yards, along a Long Island Railroad right of way," Schumer told real estate developers at a breakfast gathering organized by the New York Building Congress.

Schumer said the Related Companies, which are building the Hudson Yards neighborhood, are prepared to cooperate with Amtrak and the federal government. But Related plans to begin construction by the end of this year, making the Amtrak project especially urgent, the senior U.S. Senator from New York said.

"We will need contracts, design plans, and construction dollars to flow over the next six to twelve months to make this a reality. We need action, we need it fast," Schumer said.

The Senator said his next step will be to work to get agreements inked between the parties, so tunnel construction can begin before the end of 2013.

Schumer will also lobby for federal dollars to build the tunnels, known as the Gateway project. He estimates Gateway will require $20 million in 2013, and $100 million in 2014 for preliminary work.