A miniature mailbox sits on the counter of the Ewell Post Office in Ewell, Md. (Mark Wilson/GETTY IMAGES)

The U.S. Postal Service said Tuesday that it will delay the closure or consolidation of thousands of post offices across the country in response to requests from lawmakers, who said the process should be stopped while Congress debates legislation to overhaul the cash-strapped mail agency.

No post office or mail processing facility will be closed or merged with nearby locations until May 15 at the earliest, but officials plan to continue reviewing the fates of thousands of locations in the coming months in hopes of resuming the closures after Congress passes postal reform legislation, officials said.

“Given the Postal Service’s financial situation and the loss of mail volume, the Postal Service must continue to take all steps necessary to reduce costs and increase revenue,” USPS said in a statement Tuesday.

(RELATED: Is my post office closing? Find out!)

As part of plans to cut $20 billion in costs by 2015, the Postal Service hopes to close more than 3,700 post offices and about 250 mail processing facilities across the country. It also hopes to end Saturday mail deliveries, slow the delivery of first-class mail and change labor union contracts to possibly cut as many as 120,000 jobs.

Postal officials say the changes need to occur quickly in order to keep the delivery service solvent, but Tuesday’s move slows the process and appears to preempt efforts to force USPS to stop closing facilities by force of law.

Concerned that USPS would preempt the passage of reform legislation, 20 Democratic senators on Friday asked Senate leaders to include language in annual appropriations measures that would block USPS from closing any more facilities until a reform bill is passed.

“While some of these changes may be needed, we believe that it is very important to give Congress the opportunity to reform the Postal Service in a way that protects universal service while ensuring its financial viability for years to come,” the senators wrote.

Competing postal reform bills have passed House and Senate committees, but neither has been brought to a full vote. Sen. Joseph I. Lieberman (I-Conn.), who chairs the Senate committee with oversight of the Postal Service and is the cosponsor of the Senate measure, said Tuesday that his colleagues won’t vote on the bill this month.

“I wish it would come up before the end of the year, but there’s no time,” Lieberman said Tuesday, adding that Senate leaders told him that they hope to hold a vote on the measure early next year.

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View Photo Gallery: The cash-strapped U.S. Postal Service has announced plans to eliminate more than 250 processing centers.

Further reading:

Is my post office closing? Find facilities being reviewed for closure

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