In November 2012 the interim Financial Policy Committee recommended that the FSA takes action to ensure that the capital of UK banks and building societies reflects a proper valuation of their assets, a realistic assessment of future conduct costs and prudent calculation of risk weights. Where such action revealed that capital buffers need to be strengthened to absorb losses and sustain credit availability in the event of stress, the FSA should ensure that firms either raise capital or take steps to restructure their business and balance sheets in ways that do not hinder lending to the real economy.  . .

http://www.fsa.gov.uk/library/communication/statements/2013/methodology-note-on-calculating-capital-pressures