New York City could be getting bigger.

Mayor de Blasio on Thursday announced plans to spend $10 billion to “climate-proof” lower Manhattan by expanding the coastline by two blocks into the East River from the Brooklyn Bridge to the Battery.

“There’s nothing been done like this in the history of New York City, but it is needed,” de Blasio said.

The new shoreline would rise as high as 20 feet in some places and “act as a flood barrier” while also absorbing water, officials said.

Now all de Blasio needs is the $10 billion.

He wants the feds to put up the money, saying he hopes Democrats take the White House and loosen the purse strings.

“Perhaps after 2020 there will be a very different reality, and something like a Green New Deal moves forward with a major resiliency plank to it,” he said.

If those stars don’t align, de Blasio said, he’ll keep his fingers crossed that the US Senate flips and New York Sen. Chuck Schumer, the Democratic leader, will

help.

If Washington leaves de Blasio high and dry, the Big Apple would have to fund the plan through private development, much like Brooklyn Bridge Park across the East River and Battery Park City.

Either way, the city will create a nonprofit Battery Park City-like entity to oversee construction, officials said.

The city, state Department of Environmental Conservation and federal Coast Guard and Army Corps of Engineers must also OK the plan.

Then-Mayor Mike Bloomberg floated a similar project in 2013 to build a “multipurpose levee with raised edge elevations” following the Hurricane Sandy’s destructive floods in October 2012.