The FTSE 100 has given up the day's gains, closing in the red as US markets fell driven lower by technology stocks as fears over Apple (APPL.O) drove a wider sell-off.
The UK blue-chip index closed 13 points, or 0.2%, lower at 7,001, having reached as high as 7,070 earlier in the session.
The FTSE 100's slide began as US markets opened lower, after the Wall Street Journal reported Apple had cut production orders in recent weeks for all three of its new iPhone models.
'Given the importance of iPhone sales to Apple's bottom line, investors are understandably nervous,' said Fiona Cincotta, senior market analyst at City Index.
'Following Apple's results and its decision to no longer give a product sales break down, investors have been wary of iPhone numbers. This latest development has confirmed investor fears.'
At the time of writing, the Dow Jones was down 1.5%, the broader S&P 500 was 1.2% lower and the tech-heavy Nasdaq Composite index was 2.5% in the red.
Shares in Apple dropped 3.8%, while a wider sell-off in technology stocks took hold.
Facebook (FB.O) fell 5%, Amazon (AMZN.O) was down 4.1%, Netflix (NFLX.O) dropped 4.3% and Google owner Alphabet (GOOGL.O) traded 2.8% lower.