Bob Diamond – the former head of Barclays who tried to buy Lehman Brothers before its collapse five years ago – has joined a chorus of criticism over the lack of progress in ending banks' "too big to fail" status.
Citing "insufficient" progress in ways to safely wind down failing financial giants, Mr Diamond has called for fresh international co-ordination to end the fragmenting approach to bank regulation.
Writing in the Financial Times, the former banking boss expresses an apparent change of heart about the risks that Barclays and other banks were taking in the years before the crisis, by admitting that leverage was "too high in the boom years". He says that various regulatory advances have helped cut risk in the system but warns: "A global framework is required if we are to avoid the kind of capital regulatory arbitrage that weakened the financial system."
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Mr Diamond's comments – a rare public outing since his ejection from Barclays by regulators a year ago – reflect broader concerns among investors and officials that government powers to deal with the failure of the largest financial institutions are still inadequate.