told CBS Evening News host Scott Pelley Tuesday that he couldn't guarantee Social Security checks would go out on Aug. 3 if the debt ceiling was not raised.

"Can you tell the folks at home that no matter what happens, Social Security checks are going to go out on Aug. 3?" Pelley asked.

"This is not just Social Security checks," Obama replied. "These are veterans' checks, these are folks on disability, their checks. There are about 70 million checks that go out."

"Can you guarantee, as president, those checks will go out Aug. 3?" Pelley pressed.

"I cannot guarantee those checks go out on Aug. 3 if we haven't resolved this issue. Because there simply may not be the money in the coffers to do it," Obama explained.