usps.jpegWASHINGTON (AP) — Mired in red ink, the U.S. Postal Service is warning it will lose as much as $18.2 billion a year by 2015 unless Congress grants it new leeway to eliminate Saturday delivery, slow first-class mail by one day and raise the price of a postage stamp by as much as five cents.

In a letter to Congress, Postmaster General Patrick Donahoe described an updated five-year cost-cutting plan put together in coordination with Wall Street adviser Evercore Partners Inc. It reiterates many of the mail agency's proposals to switch to a five-day delivery schedule, raise stamp prices and close up to 252 mail-processing centers and 3,700 local post offices.

The Postal Service has already asked Congress for permission to make service cuts and reduce annual payments of about $5.5 billion to prefund retiree health benefits. But, in recent weeks, the Senate and the House have stalled on the request as lawmakers differ widely on costs, the level of financial oversight and the prospect of widespread postal closures.

In a news briefing, chief financial officer Joe Corbett said no formal proposals have been made to increase the price of a first-class stamp. He said the plan notes the additional revenue the mail agency could bring in over a single or multiyear period if it could increase stamp prices above the rate of inflation.

Since 2006, the Postal Service has increased the price of the stamp four times, from 39 cents to 45 cents.

At stake are more than 100,000 jobs, part of a postal cost-cutting plan to save some $6.5 billion a year by closing up to 252 mail-processing centers and 3,700 post offices. At the request of Congress, the cash-strapped agency agreed to wait until mid-May to begin closures so lawmakers would have time to stabilize its finances first.