The Metropolitan Transportation Authority board has approved the largest capital plan in the agency's history.

The $51.5 billion plan is set to provide a 70% increase to investments in subways, buses, the Metro-North Railroad and the Long Island Rail Road from 2020 to 2024.

Some of the investments include a massive signal project and making 70 subway stations compliant with the Americans with Disabilities Act.

The plan now goes before the capital program review board for final approval.

Gov. Andrew Cuomo issued a statement saying, "I laid out my priorities for the MTA Capital Plan to the Board several weeks ago, including improving signal technology, increasing accessibility, addressing quality of life concerns ensuring equity for LIRR and Metro-North Railroad, and upgrading bus service. This plan meets those priorities."

Mayor Bill de Blasio wrote a letter to the MTA chairman saying he would support the plan as long as the money isn't used to delay implementing congestion pricing and an audit is completed to verify costs of the plan.