NEW YORK—The U.S. General Services Administration signed a lease with the Port Authority of New York and New Jersey and the Durst Organization to occupy approximately 270,000 rentable sq. ft. of space on six floors at One World Trade Center.

With this lease, One World Trade Center will be more than 55 percent leased. Under the terms of the agreement, GSA will occupy floors 50 through 55 of the building for an initial term of 20 years starting in 2015.

The Port Authority is owner and developer of One World Trade Center, which, when completed will be the tallest building in the Western Hemisphere. The Durst Organization is an equity partner in the property and bears primary responsibility for leasing, operating and managing the building.

Currently under construction, One World Trade Center stands at 1,271 ft. tall, making it the tallest building in New York City by a difference of more than 20 ft. Upon completion, One World Trade Center will stand 1,776 ft. tall and comprise104 stories, including 69 floors of office space and an observation deck.

Construction of One World Trade Center is expected in 2013.

When complete, the new World Trade Center will include five skyscrapers; the National September 11 Memorial & Museum; The World Trade Center Transportation Hub; a center for performing arts and 550,000 sq. ft. of retail space.