The United States Postal Service will announce Wednesday that it is ending Saturday mail delivery effective August 1, in a move the cash-strapped agency hopes will offset some of the bleeding.

News of the impending cutback to five-day mail delivery was first reported by CBS News. According to CBS, only regular mail delivery will be affected; express mail, Priority Mail, and packages will still be delivered on Saturdays.

The Postal Service has been losing bales of money for years; in the 2012 fiscal year that ended last September 30, it reported losing nearly $16 billion. Ending Saturday delivery will only save about $2 billion.

“The Postal Service is advancing an important new approach to delivery that reflects the strong growth of our package business and responds to the financial realities resulting from America’s changing mailing habits,” Postmaster General Patrick Donahoe said in prepared remarks that will be delivered a press conference later today announcing the move.

By law, any changes to the Postal Service must be approved by Congress, but the decision to end Saturday delivery will get the endorsement in a letter by House Oversight Chairman Darrell Issa (R-Calif.) and Sen. Tom Coburn (R-Okla.), the ranking member of the Senate Homeland Security and Government Affairs Committee. A spokeswoman for Sen. Tom Carper (D-Del.), the chairman of the Senate Government Affairs Committee, says he is still evaluating the Postal Service’s announcement and will issue a statement later today.

But the move is sure to anger some, not least the union representing mail carriers, who have already seen their ranks thinned by 35 percent. In a statement, Fredric Rolando, the president of the National Association of Letter Carriers, called the end of Saturday delivery a “disastrous idea.”

“America’s letter carriers condemn this reckless plan in the strongest terms,” Rolando said. “We call for the immediate removal of the postmaster general, who has lost the confidence of the men and women who deliver for America every day.”