The U.S. General Services Administration is pledging its allegiance to the World Trade Centers—the new and old—by leasing out space on six floors at One World Trade Center.

The U.S. government rented space at the original towers and is looking to continue that partnership once construction is completed on the new towers, GSA communications officer Mafara Hobson says. The GSA, which handles most of the leasing for the federal government, hasn’t decided which agencies will be located in the towers yet.

Counting this new lease, the World Trade Center is now at 55 percent capacity, which will help ensure “that at least half the tower will have paying tenants when it opens in 2014,” the Associated Press reports. Publisher Conde Nast and the Vantone China Center are also reported to be leasing space at the new towers. The GSA’s lease, which was signed Wednesday with the Port Authority of New York and New Jersey and the Durst Organization, begins in 2015 and extends for 20 years.