The U.S. Postal Service announced on Wednesday that it would close more than 50 mail-processing centers this year, accelerating a consolidation plan that the agency developed to trim more than $2 billion in annual costs.

“As first-class mail declines, we must continue to improve operational efficiencies and reduce costs by making better use of space, staffing, equipment and transportation in processing the nation’s mail,” the agency said in a statement Thursday.

The Postal Service’s original consolidation plan called for closing 140 mail-processing centers during the last year and another 89 facilities starting in early 2014.

In February, the agency, which lost nearly $16 billion last year, announced that it would end Saturday mail delivery in an effort to save $2 billion annually.

(Matt Rourke/AP) (Matt Rourke/AP)

Some of the Postal Service’s financial difficulties are due to a 2006 congressional mandate that requires the agency to pre-fund 75 years worth of retiree benefits within a decade. That statute cost the post office about $1.4 billion during the last quarter alone, according to the agency’s financial report.

Postal Service officials have urged Congress to end the mandate and enact legislation to overhaul the agency.

Sen. Tom Carper (D-Del.), chairman of the Senate committee that oversees the Postal Service, issued a lukewarm response to the post office’s accelerated plan, saying it is “hard to condemn.”

“The hard truth is that these piecemeal efforts undertaken by the Postal Service are likely not enough on their own to fundamentally fix the Postal Service’s serious financial problems,” Carper said, adding that he will work with colleagues in both chambers of Congress to enact a comprehensive plan for overhauling the agency.

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