David Cameron has said that accountability for the rate-fixing at Barclays has to go “to the very top”. George Osborne called what happened "completely unacceptable" and "symptomatic of a financial system that elevated greed above all". Vince Cable said that Diamond could be prevented from running a company in the future, saying that “There are last resort powers of director disqualification – that is certainly a sanction open to us.” Ed Miliband has called for a criminal investigation.

However, despite the political pressure piling up on him and his company, Barclays chief Bob Diamond has yet to offer any sort of apology. In a letter to Andrew Tyrie, the chair of the Treasury Select Committee, he says:

Barclays traders attempted to influence the bank’s submissions in order to try to benefit their own desks’ trading position. This is, of course, wholly inappropriate behaviour… This inappropriate conduct was limited to a small number of people relative to the size of Barclays trading operations, and the authorities found no evidence that anyone more senior than the immediate desk supervisors was aware of the requests by traders, at the time that they were made. Nonetheless, it is clear that the control systems in place at the time were not strong enough and should have been much better.

Later in the letter (read it in full here) he addresses the accusations of Libor rate-setting, and admits:

Even taking account of the abnormal market conditions at the height of the financial crisis, and that the motivation was to protect the bank, not to influence the ultimate rate, I accept that the decision to lower submissions was wrong.

Neither of these “admissions” comes anywhere near to being an apology, either for the actions of the bank he leads, or for the impact it has had on small business and households. The wording also subtly denies any direct responsibility for Diamond – a “wrong” decision was clearly made, but he doesn’t offer any ideas as to who made it. Stating that the “inappropriate conduct” was limited to a small group of traders also reinforces this position – it strongly recalls the “rogue reporter” claims we’re so familiar with from the phone-hacking scandal, and comes across as an attempt to prevent the blame reaching Diamond and others in the upper echelons of the company.

Diamond will appear before the Treasury Select Committee in the near future, and no doubt Tyrie and his colleagues will take him severely to task over the detail of precisely what happened and who knew what when. But for today, with senior politicians condemning him and pledging to ensure complete accountability, declining even to offer a simple apology for what was clearly a catastrophic series of errors, has just made things a whole lot worse for Bob Diamond.