Insurer Admiral (ADM.L) was the biggest faller in morning trading (at 0940) as share price dropped 7.4 per cent to 1,422p.

The group saw its share price drop despite reporting a 27 per cent year-on-year rise in its firs half pre-tax profits.

The insurer reported pre-tax profit of £160.6 million for the six months to 30 June 2010, compared with £126.9 million in the first half of 2010.

Turnover rose 53 per cent to £1.1 billion during the first half also, a 53 per cent rise from the £720.5 million reported in 2010.

Henry Engelhardt, chief executive at Admiral, said, 'It wasn't so long ago that we were pleased to report over £1 billion turnover for a full year.

'This is an incredible achievement and is credit to the hard work of everyone at Admiral.'

Engelhardt did warn of increased injury claims and related costs in the UK market.

He added, 'As one of the lowest cost providers in a commoditised market we are well placed for a future which is shaping up to be the survival of the fittest.'

However, the insurer saw its combined ratio - a key measure of the level of underwriting profit an insurer makes - jump from 89.3 per cent in the first half of 2010 to 94.2 per cent in the first six months of this year. If the level rises above 100 per cent, insurers are paying more out in claims than it is receiving in premiums.

Public services company Serco (SRP.L) saw its share price drop by 5.4 per cent to 503.5p, while Diageo (DGE.L) slipped 2.4 per cent to 1,095p.

Elsewhere, Hargreaves Lansdown (HL.L) fell 1.9 per cent to 421.5p, as British American Tobacco (BATS.L) saw share price decrease by 1.3 per cent to 2,692.5p.

At the top of the table was listed hedge fund Man Group (EMG.L), rising by 4.6 per cent to 205.2p.

Tullow Oil (TLW.L) rose 4.2 per cent to 986p, while advertising and marketing group WPP (WPP.L) was up 2.9 per cent to 597p.

Interdealer broker ICAP (ICAP.L) and Royal Bank of Scotland Group (RBS.L) both rose 2.2 per cent to 421.5p and 2,692.5p, respectively.

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