For several years, the U.S. Postal Service has been asking the Congress to change federal law and allow the Postal Service to end mail delivery on Saturday, but Congress has not acted on that and other postal reforms. Today, the Postmaster General went ahead with the schedule change anyway, saying it will save $2 billion a year.

"It's an important part of our strategy for returning back to financial stability," said Postmaster General Patrick Donahoe, who took the liberty of asking himself the first question at his Wednesday news conference.

"It is legal?" Donahoe said to chuckles from reporters.

"We can make this change," was his answer.

"Are you essentially betting that Congress won't move to stop this?" asked one reporter, as many of the questions at today's news conference centered on the legality of this announcement.

"It is our opinion that the way the laws are set right now with the Continuing Resolution that we can make this change," said Donahoe, referring to the stop gap budget that will keep the government operating until late March.

What has legally blocked today's move has been a rider on Congressional spending bills that links Monday-Saturday mail delivery to payments to the Postal Service by the federal government for services already rendered.

Usually, what has been included in yearly appropriations bills is this type of language:

"Provided further, That 6-day delivery and rural delivery of mail shall continue at not less than the 1983 level."

That was last included in a 2011 omnibus spending bill passed by the Congress, but when lawmakers did not approve the budget bills on time last year, they simply extended the current funding levels into March of this year.

And so, without that provision in the Continuing Resolution (temporary budget), the Postal Service believes it has an opening to make changes on 6-day delivery.

The initial reaction from key lawmakers in the Congress who had supported postal reform legislation was positive, as two Republicans asked Congressional leaders to accept this change and move on with other reforms to save money.

"Without major, immediate restructuring actions, annual operating deficits will increase, and the Postal Service will sink much deeper," said Sen. Tom Coburn (R-OK) and Rep. Darrell Issa (R-CA).

"Today the post office made a smart business decision," Coburn added.