Mutual insurer Standard Life yesterday stepped up its fight against a demutualisation campaign by a group of policy-holders, saying conversion to a public company would mean lower returns and higher costs for members.

Europe's largest mutual life insurer is facing a vote on demutualisation on June 27th, forced by so-called carpetbaggers, headed by Monaco-based policy-holder Fred Woollard. Mr Woollard and his supporters say members could receive windfalls of some £6,300 sterling on average from a conversion to a public company.

Standard Life has set out its case for staying mutual in a document being sent out to its 2.3 million members today. The company has 150,000 policy-holders in the Republic, of whom 70,000 stand to profit from windfalls in the event of demutualisation.

UK chief executive Mr Jim Stretton said the group was wholly committed to defending its mutual status.

"The reason we're defending the mutuality status of the company is that we believe that the company will do better for members in the future as a mutual that than it would do as a plc," he said.

Stretton said Standard Life had outperformed other publicly listed life companies in the past and, looking forward, new policy-holders would have to pay between 10 and 20 per cent more in premiums for insurance policies if the group did convert.