Some of the UK’s largest life assurers are expected to announce measures to shore up their reserves to take account of much longer life expectancy among people who are sold annuities.

The move, which would come when the companies report their full-year financial results, follows concern from the Financial Services Authority that assurers are not taking into account growing evidence that even conservative assumptions about longevity are insufficient. That message was bolstered by the actuarial profession and its regulator last summer when both warned commonly used tables can no longer be deemed prudent.