Postmaster General Patrick R. Donahoe pleaded with lawmakers Wednesday not to block his plan to drop Saturday mail delivery. (Jose Luis Magana/AP)

Postmaster General Patrick R. Donahoe pleaded with lawmakers Wednesday not to block his plan to drop Saturday mail delivery and said taxpayers could be forced into a $45 billion postal bailout in four years unless Congress gives the agency more flexibility.

“We know it’s tough taking away Saturday delivery,” Donahoe told the Senate Homeland Security and Governmental Affairs Committee a week after announcing that he would circumvent Congress to save the ailing mail system $2 billion a year. “But with the financial situation we’re faced with, there is no other answer.”

But the move to limit collection and delivery of first-class letters to five days while preserving package delivery on Saturdays drew skepticism from rural and labor-friendly lawmakers who oppose the change and questioned Donahoe’s legal authority to proceed.

“Despite what’s in the law, your lawyers are apparently saying you can cancel six-day service?” asked Sen. Carl Levin (D-Mich.), who, with Sen. Mark Pryor (D-Ark.), said he did not believe Donahoe could make the change without congressional approval.

“It is our interpretation that we are clear to move ahead on this,” Donahoe replied.

Labor leaders who testified and stand to lose tens of thousands of jobs from the end of Saturday service also said postal officials could not just end a 150-year tradition because they want to.

“Why does the Postmaster General now believe he can eliminate mail delivery without congressional approval?” asked Jeanette Dwyer, president of the National Rural Letter Carriers Association, which represents 113,000 carriers. Like other union officials, she said the change would open Saturday service to competitors, ultimately costing the Postal Service valuable revenue.

But Sen. Tom Coburn (R-Okla.) congratulated Donahoe for standing up to Congress.

“There’s really 536 postmaster generals,” the senator said, referring to members of Congress, who control the Postal Service’s finances. “The goal ought to be that there’s one. The fact is, the post office is in trouble.”

The mail agency lost $15.9 billion in the last fiscal year from declining mail volume and a congressional requirement that it set aside billions of dollars a year for health expenses of future retirees.

Postal officials first proposed scrapping Saturday delivery to Congress in 2010, but lawmakers balked. Five-day service was approved — but delayed for two years — in a larger Senate bill that passed the last Congress but stalled in the House.

Six-day mail delivery is not required by law. But Congress has included language in legislation in annual spending bills since 1983 preventing postal officials from reducing six-day service.

Donahoe hopes to take advantage of the stopgap budget funding government operations through March 27. Congress would have to reinsert the five-day prohibition into a future spending bill. But even if the language is there, postal officials said in a legal opinion sent to Congress that they are exempt from the mandate because they do not function like a typical government agency. The Postal Service is self-sustaining, except for a reimbursement every year for the cost of mail for the blind and U.S. voters overseas.

Among lawmakers who contest the legality of eliminating Saturday delivery is Rep. Gerald E. Connolly (D-Va.), who said on the House floor Wednesday that the move would result in layoffs of more than 50,000 letter carriers. That is double the number postal officials say would be lost through attrition and reduced overtime, not layoffs.

“Congressional intent on the preservation of six-day mail delivery has been clear for 30 years,” Connolly said. “It cannot be grabbed unilaterally.”

Also Wednesday, Sen. Bernard Sanders (I-Vt.) and Rep. Peter A. DeFazio (D-Ore.), who said their rural districts depend heavily on Saturday mail delivery, introduced legislation that would preserve six-day service by rescinding the payment mandate for future retirees and lifting a prohibition on new lines of postal business — including notarizing and wine and beer shipments.

Democrats and Republicans agree that the controversy has underscored the urgency for Congress to pass legislation to restructure postal operations, although they have not agreed on a path forward.

“If we are still here in this committee on Aug. 5 debating this issue and postal reform legislation, we have failed,” committee Chairman Thomas R. Carper (D-Del.) said. “I want us to get this baby done.”

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