NEW YORK (CNN/Money) - General Motors is promoting its fuel cell technology, announcing Wednesday a deal to lease a fuel cell minivan to the United States Postal Service.

The federal mail carrier will be the first company to use the GM vehicle in the United States.

"The postal service operates everywhere in the U.S., giving us maximum flexibility to expand the relationship in areas or regions where a hydrogen infrastructure gets kicked off," said Larry Burns, GM's vice president of research and development and planning, in a press release.

As part of the two-year agreement, the U.S. Postal Service will use the minivan to deliver mail in and around Washington, D.C. beginning in September.

The start date coincides with the opening of the nation's first hydrogen pump at a retail gas station in the nation's capital, which GM (GM: up $0.27 to $47.91, Research, Estimates) had its hand in promoting.

Last May, the world's No. 1 automaker and Shell Hydrogen announced a partnership to provide hydrogen for GM vehicles operating around the nation's capital.

Federal Express (FDX: up $0.74 to $78.14, Research, Estimates) and Dow Chemical have already begun using products powered by GM fuel cells. FedEx started using a GM minivan to deliver packages in Tokyo last year and Dow (DOW: down $0.34 to $38.89, Research, Estimates) is using a fuel cell to help power a chemical plant at a 30-square-mile site in Freeport, Texas.

GM would not comment on the financial terms of its deal with the U.S. Postal Service.