Congress needs to raise the debt limit and take away the "cloud of uncertainty" about the nation's ability to pay its bills, Treasury Secretary Jack Lew said in an interview broadcast Sunday.

"The fight over the debt limit in 2011 hurt the economy, even though, in the end, we saw an extension of the debt limit. We saw confidence fall, and it hurt the economy. Congress needs to do its job. It needs to finish its work on appropriation bills. It needs to pass a debt limit," Lew said on NBC's Meet The Press.

Senior lawmakers on Capitol Hill are trying to come up with must-do legislation to keep federal agencies running after Sept. 30 and prevent the possibility of a government shutdown. At issue is what is normally routine: a plug-the-gap measure to fund the government for a few weeks or months until a deal can be worked out on appropriations bills giving agencies their operating budgets for the full 2014 fiscal year, which begins Oct. 1.

However, some Democratic liberals don't want to vote to continue to fund the government at new, lower levels mandated by the automatic, across-the-board spending cuts known as sequestration. And some conservatives are making a last stand against President Barack Obama's new health care law. In addition, Senate Democrats are resistant to a $20 billion spending cut wanted by many Republicans.

Lew maintained that the president won't negotiate over the debt limit but stopped short, however, of saying that Obama would shut down the government.

"Drawing this to brinksmanship is a mistake. It's bad for the economy for it to be brinksmanship," he said.