WASHINGTON (AP) – The Postal Service is warning it will lose as much as $18.2 billion each year by 2015 if Congress doesn't give it leeway to eliminate Saturday mail delivery and make other service cuts.

In a letter to Congress, Postmaster General Patrick Donahoe describes a five-year business plan that reiterates the mail agency's proposals to switch to five-day delivery, close up to 252 mail-processing centers and 3,700 local post offices and slow delivery of first-class mail.

He says the proposals would allow the agency to save $20 billion a year by 2015 and repay its $12.9 billion debt to the Treasury.

In contrast, he says unless Congress acts soon, the Postal Service will incur significant annual losses and become a "long-term burden to the American taxpayer."

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