Prudential has said it plans to impose a deadline for complaints from customers who face a shortfall in the value of their endowment policies, according to reports.
The insurer said it would write to its 110,000 at-risk customers to inform them that they have six months from receipt of the letter to lodge their complaint.
It added that "almost all" those customers were first warned that their policies might be worth less than originally thought three years ago.
Under FSA rules, endowment holders must formally complain within three years of being informed of a possible shortfall.
Prudential's UK chief executive Nick Prettejohn said: "We believe that the time is right to draw a line under this issue and for customers to resolve any lingering concerns they may have".
Millions of UK homeowners bought endowments - investment policies designed to pay off mortgages - in the 1980s and early 1990s, only to find that the expected returns did not materialise because of poor stock market performance.
Many have since sought compensation on the grounds that the risk of lower than expected investment returns was not explained to them by the endowment provider.
Of the 110,000 Prudential customers facing a possible shortfall, 58,000 are Prudential endowment customers, while the remaining 52,000 hold endowments sold under the Scottish Amicable brand.
