Stocks ended the worst week in a year as the clock runs down on Washington leaders to reach an agreement before Uncle Sam loses the ability to borrow.

The Dow Jones industrial average <.DJI> dropped 96.87 points, or 0.79 percent, to 12,143.24. The Standard & Poor's 500 Index <.SPX> fell 8.39 points, or 0.65 percent, to 1,292.28. The Nasdaq Composite Index <.IXIC> lost 9.87 points, or 0.36 percent, to 2,756.38.

(Reporting by Chuck Mikolajczak; Editing by Kenneth Barry)