UPDATE: The FTSE has bounced back from heavy losses earlier this afternoon on the back of weak GDP figures from the US.
The index of 100 leading shares is still in the red, down 17.09 points, or 0.32%, to 5,296.86.
However this is an improvement losses at around 2pm, when news US economic growth slowed between April and June sent FTSE100 tumbling 60.65 points, or 1.14%, to 5,253.31.
The disappointing data also dragged on the Dow Jones. The US index was down 33.23 points, or 0.32%, to 10,433.93 points shortly after opening.
The latest GDP figures showed the US economy had grown by an annualised rate of just 2.4%, the US Commerce Department has said. This compares with an annual rate of 3.7% in the previous quarter.
This second quarter figure is a first estimate, and could be revised either up or down in the coming months.
However, fears have been growing about the strength of the US economic recovery, particularly the country's high unemployment rate of 9.5%.
A large increase in imports and a fall in sales of goods such as cars partly explain the fall in GDP.
European stocks also fell on the worst-than-expected US figures, though recovered later on.
The German Dax was at 6,132.53 just before 4pm, down 2.17 points or 0.04%. In France, the Cac 40 picked up after earlier falls to enter late afternoon down 2.89 points, or 0.08%, to 3,649 points.
