The Association of Consulting Actuaries, a UK pensions trade body, will petition the government today to introduce "shared risk" pension schemes to fill a space left by the closure of many final salary plans.

Pensions provision in the UK has traditionally been split between defined benefit schemes, where pensioners are pledged a fixed retirement payment, putting all the investment risk onto the employer, and defined contribution schemes, where the amount paid in by workers is fixed but the amount paid out is not.