A trader monitors the screen on a trading floor in London.

London - UK shares fell in early trade on Wednesday, mirroring losses across European markets and an overnight retreat in the US and Asia as mounting violence in Iraq spooked investors.

The London FTSE 100 benchmark index was down 0.6 percent at 09:40 SA time, to 6,742.60 points.

Year-to-date, the index is broadly flat but still hovering at seven-year highs.

Benchmark indexes in France, Germany and Italy fell 0.5 to 0.7 percent amid an escalation of the conflict in Iraq, where security forces fought rebels for control of the country's biggest oil refinery.

“This is a continuation of the 'risk-off' sentiment ... It's profit-taking from a decent run,” said Guy Foster, the head of research at Brewin Dolphin.

Meggitt, a manufacturer of aircraft parts, was the worst performer on the FTSE 100, down 3 percent after a broker downgrade from JPMorgan.

But drug company Shire, which is defending itself from a $46 billion approach by US group AbbVie, saw its shares gain 0.7 percent after it said a US court had endorsed its patents on top-selling hyperactivity drug Vyvanse.

And commercial-property firm Land Securities traded 0.5 percent higher after saying it had acquired a 30 percent stake in Bluewater, Kent for 656 million pounds ($1.1 billion).

“An interesting, significant acquisition ... that moves the focus of (Land Securities') retail portfolio towards more dominant centres,” analysts at Oriel Securities wrote in a note to clients. - Reuters