A new U.S. Postal Service contract could mean the elimination of overnight express mail from Aroostook County.

Under a new Postal Service contract due to take effect Aug. 27 with Federal Express, next-day mail delivery would no longer be available from Aroostook County and a few other rural areas around the country.

Express mail from those areas would be offered on a two-day rather than a next-day basis.

U.S. Sen. Olympia Snowe said she’s outraged that the Postal Service might offer a lower level of service to Aroostook County.

“It is simply unacceptable that Aroostook County, or any other region of the country, should have to suffer reduced levels of service from the United States Postal Service, and I am frankly shocked that the postmaster general would condone creation of a two-tiered system in the United States,” said Snowe, who sent a letter protesting the move to Postmaster General John Potter.

Federal Express has entered a seven-year, $6.3 billion contract with the Postal Service to offer shared access to its national air transportation network of about 600 planes, Snowe said.

While the Postal Service estimates the arrangement will save about $1 billion in transportation costs, it acknowledged that express-mail services in northern Maine would be offered on a two-day rather than next-day basis, the senator said.

A Postal Service official was reviewing Snowe’s comments and had no immediate response Thursday morning.

Snowe said she became involved when a small Maine company that provides express mail and other services to Presque Isle contacted her.