The State Legislature took another step forward in the long and arduous process of filling the Midtown gap in the East River Greenway two weeks ago. By passing a law that would allow a swap of land between the city and the United Nations to move forward, DNAinfo reported yesterday, Albany cleared the way for a deal to be negotiated.

Under the terms of the arrangement reported by DNAinfo’s Amy Zimmer, the city would give part of the Robert Moses Playground, located just south of the UN headquarters, to the UN, which would build a new office tower there. In return, replacement park space would be added elsewhere and a segment of the greenway could be built between the UN and the water.

The deal would also allow the city to sell two buildings it currently leases to UN-related tenants and use that money to pay for the greenway connector. Though the Parks Department says the greenway will have a functional, no-frills design, the cost is still estimated to reach $150 million.

If it comes together, the deal would lead to the creation of a north-south trunk on the East Side that would provide a continuous, safe route for biking and walking. On the West Side, the Hudson River Greenway is now the busiest bike path in the country and the cycling backbone for all of Manhattan. It currently attracts cyclists from the East Side who go out of their way for the safety of biking apart from city traffic.

The general outline of the deal has the support of the Bloomberg Administration, as well as State Senator Liz Krueger, Assemblymember Brian Kavanagh, City Council Member Daniel Garodnick, and Congresswoman Carolyn Maloney. The empowering bill still needs to be signed by Governor Andrew Cuomo to become law.

The Albany legislation includes a sunset provision. If the UN and the city don’t ink a memorandum of understanding by mid-October, the legislation will expire.

Assuming that a deal is worked out — the momentum seems to be building in that direction, but there are a lot of moving parts — a completed East River Greenway would still be many years away. A feasibility study requested by the city in April, for example, would take two years alone.