Real estate firm Cushman & Wakefield leases space on 45th floor of NYC's 1 World Trade Center

One of the world's largest, privately-held commercial real estate firms is leasing space on the 45th floor of New York City's One World Trade Center.

The 10-year lease of Cushman & Wakefield was announced Thursday by landlords the Durst Organization and the Port Authority of New York and New Jersey.

Manhattan-based Cushman & Wakefield was founded in 1917 and employs more than 16,000 professionals in 250 offices in 60 countries. The space will serve as the company's downtown headquarters.

Durst officials say the deal means the tower is now nearly 58 percent leased.

One World Trade was previously known as the Freedom Tower. It will open later this year when anchor tenant Conde Nast begins to move in.

The 1,776-foot tower is the tallest building in the United States.