Britain's largest motor insurer Direct Line Insurance Group today reported lower 2018 earnings, hit by a fall in insurance prices.

The company also warned that it would not be immune to a "disruptive Brexit" despite steps taken to mitigate the impact. 

Like its rivals, Direct Line has been hit in 2018 by steep claims stemming from extreme weather in Britain, including the hottest summer in living memory following a late winter freeze, as well as increasing competition. 

Direct Line's brands include Churchill, Green Flag and Privilege.

It said in August that Paul Geddes would step down in 2019 after a decade at the helm and the company named its chief financial officer Penny James as its CEO last week. 

The FTSE 100 firm's operating profit fell to £601.7m for the year ended December 31, from £642.8m the previous year.

Its gross written premiums were 5.3% lower at £3.21 billion. 

UK motor premiums in 2018 were pushed down by changes in the Ogden rate, used to calculate compensation for personal injuries, and the Civil Liability Bill, which includes reforms likely to reduce claims for whiplash injuries. 

Direct Line said it considered it appropriate to maintain a prudent solvency capital ratio towards the upper end of 140-180% range, for the time being, after taking into account the political and economic uncertainties including Brexit. 

The underwriter's combined operating ratio, a measure of underwriting profitability, was 91.7%in 2018 compared with 90.8% it reported a year earlier. 

A level below 100% indicates an underwriting profit.