In one of her last acts as U.S. Treasury Secretary, Janet Yellen said her agency will start taking “extraordinary measures,” or special accounting maneuvers intended to prevent the nation from hitting the debt ceiling,

U.S. Treasury Secretary Janet Yellen is warning that the government will reach its debt limit on Tuesday and will need to take “extraordinary measures” to avoid risking a potentially catastrophic default.

Treasury Secretary Janet Yellen, in a letter on Friday to congressional leaders, said the Treasury would begin using extraordinary measures Jan. 21.