[10][11][12] Governor Hochul also announced that she had directed the Port Authority of New York and New Jersey to complete an environmental review for the Cross-Harbor Rail Tunnel for freight.

[17] Opponents of the street-running segment said it would have made IBX vehicles vulnerable to delays, since trains would be restricted to 25 miles per hour (40 km/h) and run in mixed traffic.

[23][15] The MTA allocated $2.75 billion in funding for the project in its 2025–2029 Capital Plan, accounting for half the estimated cost;[24]: 54  pre-construction work was still underway in late 2024.

[18][26] The MTA simultaneously announced that it would begin the planning process for the Interborough Express after it received $67 million from the federal and state governments,[27] and in October 2024, it opened a request for proposal for the IBX's design and environmental review.

[27][28] The light rail line is to be built in two stages, the first of which would entail clearing the site, constructing tunnels and bridges, and relocating freight tracks.

[1] Reasons for the light rail choice include faster service, easier construction due to existing right of way, availability of off-the-shelf rolling stock, and a lower overall cost that is estimated at $5.5 billion, or about $48,000 per expected daily rider.