"At some point we have to say, 'Enough is enough.' We have to make tough decisions about spending beyond our means," Chambliss said in the weekly Republican radio and Internet address.
He called on President Barack Obama, House Speaker Nancy Pelosi, D.-Calif., and other Democrats to "take a step toward responsibility and restraint and reject the path of reckless spending that America is presently on."
Citing Thomas Jefferson and the Declaration of Independence, Chambliss said, "One of the most dangerous threats confronting America today doesn't come from without, but from within, and I'm talking about our national debt."
The debt, if divided among Americans, would amount to $42,000 a person, he said, noting it has climbed $2.4 trillion -- an average of $5 billion a day -- since Obama took office in January 2009.
Chambliss said much of the debt is held by nations including China and others "that often don't share our values or positions."