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

London - Britain's top share index steadied on Wednesday, as tensions between the West and Russia and the conflict in Gaza made investors cautious, although Capita and BHP Billiton saw strong gains.

Outsourcing group Capita, which runs services from the Ministry of Defence pension scheme to police radio systems, rose 3 percent after posting an 11 percent rise in first-half organic revenue.

Global miner BHP Billiton gained 1 percent after beating its own guidance for full-year iron ore output and seeing productivity gains across a number of businesses.

Capita was the top gainer on the blue-chip FTSE 100 index but the benchmark was flat at 6,797.01 points by 10:09 SA time.

“Geopolitical tensions are preventing a better market development in Europe. Markets will be dominated by consolidation moves due to the uncertainty, combined with high valuations,” UniCredit strategist Christian Stocker said.

Investors avoided strong bets due to geopolitical concerns, with the EU raising the prospect of restricting Russian access to European capital markets, defence and energy technology, and due to the conflict in Gaza, where Israeli forces pounded multiple sites.

Catalyst maker Johnson Matthey fell 2.4 percent after saying its first quarter underlying operating profit fell by 11 percent.

Energy firm SSE and London Stock Exchange dropped 3.2 percent and 1 percent respectively after going ex-dividend. They knocked a combined 2.5 points off the FTSE 100 index. - Reuters