Empire State Development is leasing five full floors at Durst Organization’s 655 Third Ave. office tower, a major boost for the city’s muted office market.

The deal is for 117K SF, Durst announced in a press release. The economic development agency will take space on the second through sixth floors of the 30-story building.

ESD's rent wasn't made public. It plans to move its New York City headquarters down the street from Rudder Property Group’s 633 Third Ave., where it leases roughly the same amount of space, a spokesperson said.

"We are proud that Empire State Development has chosen 655 Third Avenue for its New York City headquarters," Durst’s Jody Durst said in a statement. "655 Third Avenue has a prime location one block from Grand Central Terminal, offering unparalleled access to transit and convenience in New York City."

Tom Bow, Ashlea Aaron and Bailey Caliban represented Durst in-house. Moshe Sukenik and Brian Cohen of Newmark and Joan Brothers of Manhattan Boutique Real Estate represented ESD in the lease, one of the largest relocations in Midtown so far this. It was the second-largest lease in the city last month, behind a New York City agency's 640K SF lease at 110 William St., according to Colliers.

Midtown's office availability rate was flat at 16% in July, during which some 949K SF of deals were signed, a 50% year-over-year decline and a 20% dip from June, per the brokerage. The city's overall availability rate stood at 17.8%, an all-time high.

While the areas around Grand Central and Penn Station have attracted a fair number of tenants due to transportation access, the city overall has been grappling with a large amount of office supply and significantly pared-back demand.

Landlords have had to move aggressively to secure tenants. Last week, Durst sued two of its top tenants at One Bryant Park, Bank of America and law firm Akin Gump Strauss Hauer & Feld, to stop them from doing a sublease deal together at the building, also known as Bank of America Tower.