ALBANY — A liberal former state lawmaker and a conservative fiscal watchdog have joined forces — calling on the state to redirect billions of dollars in unspent legal settlement money to help fix the subways.

Former Assemblyman Richard Brodsky (D-Westchester) and E.J. McMahon, of the Empire Center for Public Policy, sent a letter outlining the idea to Gov. Cuomo, legislative leaders, and new MTA Chairman Joseph Lhota.

“With this letter, we are suggesting action well within your practical abilities to help swiftly address the financial needs of the system, even as the more time-consuming engineering and construction challenges are worked out,” Brodsky and McMahon wrote.

The two said that half of the $10 billion the state received since 2014 as part of legal settlements with the financial sector has yet to be spent, though much of it has been committed to non-infrastructure uses, including $2 billion for a variety of upstate economic development projects.

Brodsky and McMahon are suggesting the state redirect at least $4 billion of the remaining funds to create an “Emergency Repair and Maintenance Program” divided between needed New York City transit upgrades and highway and bridge work in the rest of the state.

“It is essential that such a program be focused on bringing these systems to a ‘State of Good Repair,’” they wrote.

They also suggested the MTA consider a capital plan amendment to take into account the extra funds.

“As the Governor previously said, the current state of the system is unacceptable and New Yorkers deserve better,” Cuomo spokeswoman Dani Lever. “Joe Lhota is a proven manager and the state will provide the MTA with the support it needs to address the fundamental issues plaguing the system.”

A Cuomo aide added that the settlement funding has already been allocated by the legislature in statue and is going to fund things like Penn Station access, supportive housing, cancer research and treatment, ‎poverty reduction and health care.The letter comes at a time when the subway system has been plagued by delays and other problems. The latest mishap took place Tuesday morning when an A train derailed in Harlem because of a poorly secured loose rail.

McMahon and Brodsky suggested the issue could be taken up at a special legislative session Cuomo called for Wednesday.

Assembly Speaker Carl Heastie, when asked if the MTA problems could be addressed at the special session, said there wasn’t enough time.

“I think that the issue for the MTA is around infrastructure and funding, and I don’t know if we can get that answer in, you know, two hours,” he said.

State Sen. Michael Gianaris (D-Queens) said the McMahon-Brodsky plan would be helpful but wouldn’t provide all the funds the MTA needs to right the system. Gianaris, as first reported by the Daily News on June 19, has his own proposal that would impose temporary taxes on millionaires in the 12-county MTA region and city hotels to raise at least $6 billion over three years for needed MTA projects.

“The MTA needs an infusion of funding to make up for years of being short-changed,” Gianaris said. “I put forward an idea I think is fair and equitable. If others have ideas, I’m all for it. The key is stopping the bleeding and fixing the system.”