The City watchdog is urging consumers to act now if they think they may have been mis-sold an endowment mortgage.

The call came as the Financial Services Authority (FSA) confirmed it was relaxing the time limit in which people have to lodge a potential endowment mis-selling claim.

But the regulator warned some consumers could still have only days left to complain.

The Financial Ombudsman Service will only consider complaints if they are lodged within three years of a consumer first becoming aware they had suffered a loss as a result of being mis-sold a policy.

For endowment policies this time is seen to be when the holder received their first reprojection letter telling them if they faced a shortfall in the maturity value of their policy.

The first round of these letters was sent out in early 2000, meaning the time limit for complaints for thousands of people runs out this year.

However, the FSA has stated that only a red reprojection letter, which warns that consumers will almost certainly face a shortfall, will now be seen as the time they first became aware of the problem, and not amber letters, which warn there may be a problem, or green ones which mean the policy is on track.

It added consumers would also not be considered to have run out of time until six months after they received a second reprojection letter.

But the regulator warned anyone who received a red letter in February 2000 and a second letter more than six months ago could have just days left to complain.