Massport is seeking proposals from developers to build a “signature office development” next to World Trade Center Station on the MBTA’s Silver Line.

Along with opportunities to build on the 1.1-acre parcel A-2, which is currently used as surface parking, developers will be given an option to build an 11,500-square-foot air rights portion above the Massachusetts Turnpike’s exit 25 off-ramp, which terminates at Congress Street.

A request for proposals due May 14 seeks experienced developers and encourages applicants to make diversity a priority when assembling their project teams.

The RFP emphasizes the site’s transit and highway connections, including a ramp at the southeast corner that will connect to the westbound Turnpike and Massport Haul Road. The office buildings could be designed with entrances both on Congress Street and the World Trade Center Avenue viaduct, which runs past the eastern side of the property.

But the property also has limitations. A portion of the 50-foot-wide Silver Line tunnel runs beneath it, potentially complicating design of underground parking. And maximum building heights are limited to 269 feet because of Logan International Airport flight paths.

The site is virtually surrounded by large-scale residential and commercial projects on the Seaport’s dwindling undeveloped land. The project would become the fifth active development project on Massport-owned land in the Seaport District.

The agency is building a 1,550-space parking garage and transportation center on D Street, and private developers are moving forward with a 302-unit apartment complex and 294-room Hyatt Place hotel on Northern Avenue, a 24-story apartment tower on Congress Street and a 1,054-room hotel across from the Boston Convention and Exhibition Center, all on parcels leased from Massport.

Two large residential developments, the 733-unit Echelon Seaport and the 414-unit 399 Congress St., are under construction just west of the property on privately owned parcels.