The UK Shareholders Association was quick to point out that “all savers have lost out from the financial crisis in banks and the impact it has had on the wider economy”.

But Gordon Brown has conveniently blanked the thousands of British savers who woke up a year ago this week to find their life savings had been seized by the UK Government – and have yet to be returned.

Many have lost six-figure sums, some because they had large amounts on deposit following property sales. There has been human distress among retirees, families and single people who have lost much of what they worked for, and at least one suicide.

They are British expatriates, whose first mistake was to follow their work abroad, and to save. Their UK banks told them money laundering rules meant they would need to move their cash offshore. Their second mistake was to choose the Derbyshire Building Society’s offshore account, based in the Isle of Man. But the Derbyshire, now part of Nationwide, sold the business at the end of 2007 to Icelandic bank Kaupthing hf, which had already bought the UK merchant bank Singer & Friedlander in London. The renamed Kaupthing Singer & Friedlander Isle of Man (KSFIoM) pledged their new customers a ‘parent company guarantee’ on behalf of Kaupthing hf – a bank approved by the Financial Services Authority to operate in London. The expatriates’ third mistake was to trust the global banking system.

Singapore-based Mike and Carol Harrison, whose son Nick is a business manager for a major drugs group in Glasgow, had their £270,000 life savings in the bank and currently expect to get only £100,000 back.

Mike told The Herald a year ago they had opened their account with the Derbyshire 15 years ago, saying: “We are not into high-risk securities, it was a building society.” On a visit home in 1996, he tried to open a UK savings account, but every bank turned him away. “Without a UK utilities bill, they wouldn’t entertain it.”

He added: “When we heard the news it was like being told you have a terminal illness.”

Carol said last month that her husband is “not the same person” since the shock hit.

Six months ago the FSA said it proposed to lift the £50,000 limit on the Financial Services Compensation Scheme to £500,000 for a six-month period, where a large deposit had been made for a specific reason.

But that will not help the likes of KSFIoM victim Stephen Thomas, who said: “I have worked in Russia for over 10 years in the construction industry. In July last year I sold my business and house to return to the UK. We deposited the proceeds, over $722,500, in the Isle of Man bank in early September – no onshore bank would take our money because we were not yet resident in the UK. Can you imagine how we felt when our bank ceased trading and was put into administration?”

A year on, questions remain about the role of the Treasury and the Financial Services Authority in the forgotten banking disaster.

On October 8 2008, as the banking crisis swelled, the UK Government used anti-terrorist legislation to freeze the assets of Kaupthing Singer & Friedlander in London.

The Transfer Order issued by the Treasury was a detailed document specifically designed for the seizure and break-up of KSF. “This represented the springing of a contingency plan which must have been several months in the making,” the depositors’ action group commented in its submission to the Treasury Committee of MPs earlier this year.

Days earlier, the Isle of Man’s Financial Services Commission (FSC) had taken a fateful decision to intervene in the affairs of Kaupthing by removing some £532m, two-thirds of the £820m of assets held by KSFIoM, from Kaupthing in Iceland to KSF in London – for safety.

The FSC told the treasury committee inquiry: “Funds were placed with KSF on the understanding that any exposure to the remainder of the Kaupthing group would be contained within the prescribed UK regulatory policies…..where all related party exposures were limited to 25% of ‘large exposure capital base’.”

However, the FSC has since discovered that KSF was owed £900m by its Icelandic parent – which it estimates to be 150% of the capital base, suggesting that the FSA’s rules “were either not applied, or were subsequently relaxed significantly, or were breached in a significant manner”.

The Treasury’s order gave special powers for the assets within KSF to be used for an “overriding objective” – to underwrite the transfer in full to Dutch bank ING of £2.6bn of deposits made by 170,000 UK savers with Kaupthing Edge – the Icelandic bank’s high-interest savings brand.

KSF’s balance sheet showed a value of £8bn in its last accounts. KSFIoM, now in forced administration, is owed £400m – which would enable it to repay all depositors in full, according to the provisional liquidator Mike Simpson, of PricewaterhouseCoopers. But Simpson and the Manx regulator John Spellman have met with a wall of secrecy around the administration which they say flouts the Isle of Man bank’s rights as a principal creditor. Spellman told The Herald he was given “no information whatsoever” on the value or nature of the assets seized by the Treasury.

Tony Shearer, the former chief executive of Singer & Friedlander, told MPs he had flagged to the FSA in 2005 that Kaupthing was an unfit owner of the niche UK bank. He has more recently analysed the Kaupthing corporate loan book at September 2008, viewable on the internet, which shows around £6bn loaned to only 200 entities. Shearer said: “No sensible bank would have lent these sorts of amounts to such a very narrow customer base, drawn mainly from Iceland and including some very entrepreneurial characters. In almost all cases the security described is inadequate and in most cases simply does not exist.”

Of the FSA’s claim to the committee that its “passporting” of overseas banks did not oblige it to exercise oversight, Shearer said: “The FSA had the ability to talk to the Icelandic regulator to help it regulate the entity properly and had every opportunity to warn its political master of the issues. I do not yet know whether they did any of these things as they have so far refused my Freedom of Information requests.”

Only three-quarters of the 10,000 KSFIoM depositors, those with under £50,000, will eventually get their money back under a delayed and previously unfunded Manx compensation scheme.

All 400,000 UK-based savers with the Icelandic banks mainly Icesave, and more with Bradford & Bingley Isle of Man, have been repaid all their cash, no matter how much they deposited. Last month the Icelandic government even promised to repay over time the £3bn cost to the UK and Dutch governments of that compensation. Yet the remaining Isle of Man savers, as well as bondholders with the likes of Aegon Scottish Equitable who stand to lose up to 27% of their money, and in common with charities and local authorities, are still out in the cold.

The Treasury’s even colder response is that KSFIoM “could have chosen to deposit its money elsewhere”.

Despite the PM’s boast, some £1.6bn in total of British-owned cash may have been lost, non-repayable, in Iceland.