Mrs Liddell has singled out the Sedgwick group and Legal and General for criticism, and warned another 22 leading pensions companies that the Government will not tolerate further foot-dragging.

“This is your last chance to demonstrate that the industry can be trusted,” she told the companies.

Teacher unions representing members who were persuaded to exchange their inflation-proofed occupational pensions for inferior private pensions have given Mrs Liddell’s tough talk a cautious welcome. Marion Bird, deputy head of pensions at the Association of Teachers and Lecturers, which estimates that up to 1,000 of its members were mis-sold pensions, says she is not convinced that pension firms will be goaded into action.

But she is delighted that Legal and General has been targeted by the minister. She cites the example of an ATL member who first claimed compensation from Legal and General in January 1994 and is now about to retire early on ill-health grounds without knowing when he will receive a full pension.

“I have dealt with several cases involving Legal and General’s pensions and I have felt that they have not reacted to the seriousness of the cases or if they have reacted, it’s been at absolutely the eleventh hour.”

Legal and General says it is working as quickly as possible to restore victims of mis-selling to their occupational pension schemes. But a company spokesman says it needs the help of the occupational pension schemes themselves, which are often slow to provide information on individual cases.

Teachers’ Pensions, the Government agency responsible for the Teachers’ Superannuation Scheme, was unable to say how long it usually takes to provide insurance companies with this information. However, the agency has now supplied informatio n on the cases of 3,350 teachers, of whom only about 320 have so far been reinstated in the superannuation scheme.

Sedgwick and Legal and General are unlikely to be the last companies to be publicly named in connection with the pensions scandal. Helen Liddell has told companies they must provide her with regular updates on their progress and that she intends to publish this information. She has also threatened to take further action against them if she is not convinced of their good intentions.

Some pensions firms have already taken steps to speed up their reviews. These include Pearl Assurance, which has 400 teachers among the 250,000 customers who were persuaded to opt out or not join their occupational pension schemes in the late 1980s and early 1990s. The company has seconded a general manager to head the review full-time and has set aside 25,000 hours of actuarial time to do the job.

If the other 23 companies named by the Treasury follow Pearl’s lead, many of the teachers and other employees sold inferior personal pensions could receive compensation sooner rather than later. But those who bought their pensions from independent financial advisers may have a longer wait, according to the ATL and the National Association of Schoolmasters Union of Women Teachers, both of which have started legal proceedings against firms of advisers.

“It’s interesting that the Government is looking at the large insurance companies,” says Brian Clegg, assistant secretary for salaries and pensions at the NASUWT. “But our message to Helen Liddell is that there’s an even bigger concern with

small independent financial advisers who have taken people out of the teachers’ pension scheme and are doing even less about reinstating them than the insurance companies. ”

The Independent Financial Advisers’ Association strongly repudiates this claim. But while there is no evidence that personal pensions are still being mis-sold, the National Union of Teachers, the ATL and the NASUWT all say that new cases still come to light whenever the matter hits the headlines.

One reason why teachers are often slow to come forward is that they have to admit they were taken in by smooth-talking salesmen. Brian Clegg warns that these teachers will end up with inadequate pensions unless they act soon.

“There are various time limits within which claims for bad financial advice have to be pursued and they are rapidly running out,” he says. “People who haven’t got their union involved thus far are really getting into a situation where it’s very difficult to help them. ”

The 24 pensions providers named by the Treasury are: Abbey Life, Allied Dunbar, Barclays, Britannic, Colonial, Co-operative Insurance, Equitable Life, GAN, Guardian, Hogg Robinson, Legal and General, Lincoln International, LloydsTSB, London and Manchester, NatWest, Norwich Union, Pearl, Prudential, Royal Sun Alliance, Royal London, Sedgwick, Sun Life of Canada, United Assurance, and Windsor Life