The Daily Telegraph newspaper reports that because of a computer blunder, the Inland Revenue is going to have to issue 10 million letters telling people to top-up their pensions.

The IR would have sent these letters as a matter of course to over the five years from 1996 to 2001, but because of a glitch during a computer system changeover, people have not been reminded that their pension payments had fallen behind.

People should have been advised about making up their National Insurance contributions to qualify for the minimum state pension of £77.45 a week. Reminders are normally sent out to those workers who fall short of the minimum £4,625 per annum income necessary to contribute a full year's National Insurance contributions.

Many people will be advised to pay up to £1,500 in extra contributions if they wish to make up their pensions but only around 4% normally choose to make the top-up payments.

An Inland Revenue spokesman told the newspaper that to make up for the error, the deadline for top-up payments for the five years in question had been extended to April 2008.

He said: "Because people were not made aware of the fact that they could make additional contributions if they wished, the law does allow us to extend the deadline to make these additional contributions.”

"No one is going to be out of pocket because they are going to be given longer to make the extra contributions. We are very sorry if anyone has been inconvenienced."

However, it is mostly low paid workers who would have got the notices and those near to retirement will find it most difficult to pay the top-up.