U.S. Treasury Secretary Janet Yellen said on Friday that a potential U.S. default could cause a global financial crisis and undermine the role of the dollar as a reserve currency. The U.S. government hit its $31.4 trillion borrowing limit on Thursday, a figure that reflects money already spent by the government. Yellen has informed congressional leaders that her department had begun using extraordinary cash management measures that could stave off default until June 5.
