"The post office is incurring daily deficits of $25 million on top of its debt of more than $13 billion," he added.

Bartlett's comments are the latest sign that Republicans will largely ignore the Senate-approved bill, S. 1789, and take up their own bill from House Oversight and Government Reform Committee Chairman Darrell Issa (R-Calif.), possibly as early as next week.

The Senate bill would return some of the money that the USPS overpaid into its retirement fund, and require some of that money to be used to pay for the early retirement of thousands of USPS workers. It also delays for two years plans by the USPS to start closing offices.

Republicans have said the bill would essentially require taxpayers to bail out the USPS, by giving $11.4 billion back to USPS from Treasury and letting USPS defer $23 billion in payments for a retiree health benefit plan.

Among other things, Issa's bill would set up a commission to recommend office closures, allow USPS to quickly end Saturday delivery and make other adjustments aimed at shoring up USPS's finances.

Senate Democrats have pushed House Republicans to take up some form of postal reform bill soon, so the House and Senate can reconcile their two bills in some way by May 15, when USPS is expected to start closing offices.