Minutes of last month's meeting of the Federal Reserve's open market committee have raised the prospect of a third round of quantitative easing to boost the US's sluggish recovery.
US Federal Reserve chairman Ben Bernanke has told Congress the US economy is "close to faltering" and more action may be needed.
The Federal Reserve's latest cunning plan seems to have been misinterpreted by many, but not by Mr Market. This is less of a money-printing exercise, á la QE1 and QE2, than an attempt to flatten the yield curve.
Investors have accused the Federal Reserve of ‘fiddling while Rome burns' after its latest attempt to support the US economy was followed by a brutal market sell-off.
European markets fell back into the red on Friday as investor concerns about the global economy returned.
(Updated) The FTSE 100 was well below 5,100 late morning as investors sold off shares following the Fed's latest move to stimulate the US economy.
Operation Twist - the Federal Reserve's latest attempt to boost economic growth in the US - sent markets globally tumbling overnight, with major indices in the US and Asia shedding up to 3%.
The Federal Reserve will not pump extra money into the ailing US economy, but policymakers last night unveiled a new scheme which they hope will stimulate growth.
The FTSE 100 dipped in early trading after a muted session for markets overnight, as investors await news on quantitative easing in the US and the UK, and as the European Union's Greek bailout talks continued.
Alliance Trust's head of fixed income says the only way is up for yields on gilts and treasuries amid record lows.