Debt ceiling clock starts ticking: The U.S. could run out of money to pay its bills as early as mid-December

The country will most likely no longer be able to meet all of its debt obligations and hit the so-called X date between mid-December and mid-February, according to a new estimate from the Bipartisan Policy Center. If lawmakers don't address the debt ceiling, the U.S. would go into default for the first time, which economists warn would be catastrophic for the global economy.

Earlier this month, Congress moved to raise the debt limit by $480 billion, which would allow the government to keep paying the bills through early December. But in a letter to congressional leaders last week, Treasury Secretary Janet Yellen said the department will need to keep using so-called extraordinary measures, such as not investing in some retirement funds and suspending the sale of some securities. She said it was "imperative" for Congress to act.

"The 11th-hour deal to raise the debt limit just days before the X date did stave off catastrophe, but it was only a temporary fix," said Shai Akabas, director of economic policy at the Bipartisan Policy Center. "With another debt limit crisis on the horizon in a few short months, the clock is ticking for Congress to once again protect the full faith and credit of the United States."