The head of the US Federal Reserve, Ben Bernanke, has said America's creditworthiness is at risk if the country's borrowing limit is not raised.
The Federal Reserve chairman has urged Republican members of Congress to vote in favour of lifting the borrowing level from its current $14.3 trillion threshold.
If agreement is not reached by a deadline of August 2, the US could start defaulting on its obligations.
Mr Bernanke warned about the short-term effects of such a development.
'I fully understand the desire to use the debt limit deadline to force some necessary and difficult fiscal policy adjustments, but the debt limit is the wrong tool for that important job,' Bernanke said in a speech in Washington.
'Failing to raise the debt ceiling in a timely way would be self-defeating if the objective is to chart a course toward a better fiscal situation for our nation.'
