"The President has made clear he's not going to negotiate over raising the debt ceiling. It is an obligation that Congress retains for itself," Carney said at the daily briefing.

　　"We have to pay our bills. We're the United States of America; we are not a third-tier economy that goes month to month or every half year and casting doubt on whether or not we're going to meet our obligations. That's not who we are," he noted.

　　Some Republicans including U.S. House Budget Committee Chairman Paul Ryan have floated the idea of a short-term extension of U.S. government's borrowing authority, in a move to use a government default or shutdown as the bargaining chip to push for government spending cuts.

　　There is a long tradition for Congress acting to raise the debt ceiling, and Congress should do it "without drama and delay", Carney stressed.

　　At a press conference earlier this week, Obama urged Congress to raise the country's debt ceiling in a timely manner to avert dampening investor confidence and derailing the economic recovery.

　　The U.S. federal government reached its debt limit of 16.4 trillion U.S. dollars on Dec. 31, 2012, and the Treasury Department was taking extraordinary measures to temporarily postpone the date of a possible default. The U.S. government is expected to run out of ways to meet all of its obligations between mid-February and early March.