Threat of debt default hangs over US
So far Wall Street has brushed off worries about the deadline to do a deal on America's borrowing limit.
But the pressure is mounting - the US dollar has weakened and the concern about the once unthinkable default is growing.
Analysts are starting to crunch the numbers for the US losing its triple-A credit rating.
JP Morgan estimates it could cost the government $100bn a year.
Caroline Hepker reports.