The head of the financially struggling U.S. Postal Service said the agency must be allowed to ease the terms of prepayments into a retiree health-care fund and eliminate general mail delivery on Saturday.

Patrick Donahoe told "CBS This Morning" the agency isn't asking Congress for money.

He said, "I think most people don't realize, we're 100 percent self-sufficient. We pay our own way." But the postal chief notes the agency is losing $15.9 billion this year.

Donahoe says the post office needs to refinance retirement health fund payments to $1 billion a year instead of $5 billion.