U.S. Postal Service debt: Postal Service reports $5.2 billion loss in 3rd quarter

From April to June, losses were $2.1 billion more than during the same period in 2011.

The mail agency said it is being hurt significantly by mounting costs for future retiree health benefits. Those expenses made up $3.1 billion of the post office's quarterly loss.

Declining first-class mail volume also contributed to losses.

The Postal Service for months has been urging Congress to pass legislation that would allow it to eliminate Saturday mail delivery and reduce the annual health payment of $5 billion. The post office defaulted on that payment last week after the House failed to take action.

The mail agency says it will miss a second $5.6 billion payment due next month as cash runs low.