Testifying before a joint Assembly-Senate budget hearing on Thursday, Thruway Authority Executive Director Tom Madison acknowledged a financial plan for replacing the Tappan Zee Bridge is yet to be finalized.

“We do not have a complete financing plan for the bridge,” Madison told lawmakers. “What we have, and what I was mentioning earlier, is the intent to empanel this toll and financing task force.”

This drew a skeptical response from legislators on the budget panel, who questioned Madison why state is yet to have a clear picture of how the $3.9 billion project will be paid for.

A major point of contention is how much tolls on the bridge — and possibly throughout the Thruway system statewide — will increase in order to fund the project.

“So a $3 point something billion project is going on and you’re just estimating that possibly the tolls will cover the financing, but there is no plan?” Senate Finance Committee Chairman John DeFrancisco said. “And there’s going to be a group that comes together to try to figure out a plan after the fact?”

The Syracuse Republican wondered if there was a “back-up plan” in case revenue from tolls on the system wasn’t sufficient.

“They will be sufficient,” Madison said.

DeFrancisco responded: “OK, you heard it here.”

Gov. Andrew Cuomo fast-tracked construction of a new bridge when he took office 2011, clearly multiple environmental and design hurdles that had slowed progress over the last decade to replacing the present structure.

The state was approved for a $1.6 billion low-interest federal loan to finance part of the massive construction project, which will build a new span to connect Westchester and Rockland counties at the Hudson River.

State officials on Thursday announced one of the largest water-based cranes in the world had arrived in the Port of New York and New Jersey. The crane was dubbed “I Lift NY.”