London-based sandwich-and-coffee chain Pret a Manger has a deal to occupy the ground-floor retail space at the Graham building office tower near City Hall, which is under contract to be sold.

Pret, as it is popularly referred to, has a lease for a 1,780-square-foot store at the 30 S. 15th St. building, which it hopes to open by the end of the year, Jacob Cooper, a partner with brokerage MSC Retail, said in an email last week.

The restaurant, which already has locations at 30th Street Station and on the University of Pennsylvania campus, “is aggressively pursuing an expansion in Center City,” said Cooper, who represented the chain in the deal, alongside colleague Brittany Goldberg.

Pret, a subsidiary of Luxembourg-based Jab Holding Co., has more than 530 shops nationwide, primarily in the United Kingdom, the United States and Hong Kong. Most of its U.S. shops are in New York, Chicago and Washington.

At the Graham building, it will replace Parliament Espresso and Coffee Bar, owned by Constellation Catering.

News of the chain’s arrival comes as the tower’s owner, an affiliate of Philadelphia-based Grasso Holdings, prepares to sell the property, which is named for its anchor tenant, insurer Graham Co.

Doug Rodio, who has been marketing the 25-story, 243,750-square-foot tower as a senior managing director at commercial real estate firm JLL in Philadelphia, said the building is under agreement to be sold but, citing terms of the contract, would not identify the buyer or discuss its purchase price.