[Yellen: if the debt ceiling cannot be raised, the United States will have to default on certain payments] FAP, Friday (May 12), local time, U.S. Treasury Secretary Yellen said that if Congress fails to raise the debt ceiling, the federal government will have to default on certain payments. "if Congress fails to do that, it will really damage our credit rating," Yellen said in an interview. We will have to default on certain obligations, whether it's national debt payments or payments to social security recipients. " Ms Yellen added that this was something the US had not done since 1789 and should not set a precedent now.