LONDON: Europe's main stock markets climbed at the open on Wednesday, as investors awaited the outcome of the US Federal Reserve's latest monetary policy meeting.

London's benchmark FTSE 100 index added 0.24 percent to 6,783.13 points, Frankfurt's DAX 30 advanced 0.12 percent to 9,932.04 points and in Paris the CAC 40 gained 0.10 percent to 4,540.63 compared with Tuesday's closing level.

All three main indices had inched higher on Tuesday as investors awaited this week's US Federal Reserve policy meeting, but fears that violence in Iraq could disrupt energy supplies still weighed on sentiment.