The Association of British Insurers (ABI), headed by former Aegon UK chief executive Otto Thoresen, is undertaking the most wide-ranging probe ever into the challenge the country faces in paying for its ageing population.

The ABI wants to hear from consumers and groups representing them - pension experts, think-tanks, health bodies, unions and politicians - on how a new approach "fit for the future" can be found.

With nearly 11 million people in the UK aged over 65, and this figure expected to surge to 16 million in the next 20 years, many people will spend more time in retirement than they did paying off their mortgage.

Mr Thoresen, ABI director general, said "radical reform" was needed.

A survey on ABI's website will ask people about areas such as state benefits, how much money they think they need to live on in retirement and their level of knowledge about different financial options. The consultation will close on December 20 and the issues will be discussed in workshops before a report is next spring.

The survey is at abi.org.uk/retirementsurvey.