US President Barack Obama and the chief economist of the International Monetary Fund (IMF) each issued separate warnings to ultra-conservatives in congress who may or may not understand that they are playing with fire in holding up raising the US debt limit.

“If reasonable Republicans want to talk about these things again, I'm ready to head up to the Hill and try,” Obama told reporters at the White House.

“But I'm not going to do it until the more extreme parts of the Republican Party stop forcing (House Speaker) John Boehner to issue threats about our economy. We can't make extortion routine as part of our democracy.”

A bipartisan majority exists to pass a spending plan and a measure to raise the debt limit.  But Boehner has refused to bring a simple spending resolution up for a vote in order to try and extract policy concessions from the President, who isn’t budging.  As a result, the US government has shut down.  Now Boehner is threatening to do the same thing with the US debt limit, a term that simply means paying back existing debt, not incurring new debt.

A failure by Congress to raise the nation's borrowing limit “could severely damage the global economy,” according to IMF chief economist Olivier Blanchard, “Prolonged failure would lead to an extreme fiscal consolidation and almost surely derail the U.S. recovery.  But the effect of any failure to repay the debt would be felt right away, leading to potential major disruptions in financial markets, both in the United States and abroad,” Blanchard stated.