The design-build method of contracting being used on the replacement of the Tappan Zee Bridge on the Hudson River should go statewide, Gov. Andrew Cuomo said on Monday while visiting the construction site.

Though using the method, which streamlines and unifies the contracting process on construction projects, has saved $1 billion according to state estimates, a final price tag for the new bridge remains elusive, Cuomo said.

But the plan announced on Monday from Cuomo is one of a handful of policy proposals the Democratic incumbent has made over the last several weeks as he runs for re-election.

“I’m going to propose to the Legislature in January that we take that design-build system and we use it for all government construction projects and all acquisition projects,” Cuomo told reporters.

The initial design-build legislation for the Tappan Zee Bridge replacement was first approved in December 2011, when state lawmakers and Cuomo agreed on a package of measures that included changes to the state’s tax code.

At the time, business groups called for the design-build legislation to be made a statewide component of construction projects.

“It makes sense,” Cuomo said today. “Government does not do well when it comes to building projects like this itself. Let the private sector build, let the government get the best price and that’s what this design-build legislation is all about.”

But a final cost for the bridge — as well as what tolls will be — is unclear.

Funding the new bridge — estimated to cost $4 billion — became more complicated last month when the federal government prevented the state from borrowing most of a $500 million loan from a clean-water revolving fund.

Cuomo’s office had initially said the loan was a key piece of the project in order to keep tolls low, but the governor has since downplayed the loan’s significance.

Cuomo today said more factors are at work determining the final cost of the bridge, including whether any more federal funding can come through as well as the schedule for the construction.

“We’re also fighting for federal funding and depending on what federal funding we get, that would then reduce the tolls. We need a little more specific information before we can come with a cost of the bridge,” Cuomo said.

He insisted a decision on tolls is not being held up because of the upcoming gubernatorial election against Republican Rob Astorino, the Westchester county executive.

“Remember, we’re talking about four years down the road this bridge is going to be completed,” Cuomo said.