Market Street West seems to have the makings of a steakhouse district.

A proposed addition to the 1700 Market St. office building would house a high-end steakhouse, its moderate-priced Mexican sibling, and a casual restaurant.

The city zoning board will be asked to approve the plan for a three-story structure - topped with a roof deck - that would occupy a present plaza along 17th Street between Ludlow and Market Streets. The existing building is set back from the streets.

A representative of Consolidated Restaurant Operations confirmed that III Forks - its steakhouse/seafood restaurant with nine locations nationwide - and Cantina Laredo - Consolidated's Mexican restaurant with a branch in King of Prussia - would be tenants.

DAS Architects is the designer. Renderings posted on its website show a gleaming, glassed-in structure bearing signs for III Forks, Cantina Laredo and Honeygrow, a local fast-casual restaurant. Contacted this week, Justin Rosenberg of Honeygrow said he knew nothing of the project.

Plans are due to be heard soon by Center City Residents' Association in advance of a May 13 appearance before the zoning board. Ronald Patterson of Klehr Harrison represents the building owner.

A timeline was not available, but it's believed that an opening is targeted before the Democratic National Convention in 2016.

The neighborhood's residential complement is being beefed up, as is its steakhouse lineup. III Forks would join a planned relocation of Ruth's Chris steakhouse to the Sonesta Hotel a block away, at 18th and Market. Also nearby are Chops, also a block away, at the Comcast Center at 17th Street and JFK Boulevard. Italian steakhouse Davio's is at 17th and Chestnut, also a block away.