Lord Levene of Portsoken is to take over at the 314-year-old insurance market at the end of the year.

He replaces Sax Riley, who is retiring after two years in the job.

The announcement comes weeks after the market admitted the 11 September attacks had cost it almost £2bn, helping push it to its third consecutive annual loss.

Mr Riley said Lord Levene's appointment was part of an attempt to modernise the market and address criticisms it was too inward looking.

Lord Levene, a former lord mayor of the City of London, is vice-chairman of Deutsche Bank and a director of Sainsbury's.