It is peculiar that one of the strongest and most vocal supporters of the City of London is not in fact British, but rather an anglophile American who has made the UK his home for more than a decade.

For a second time in days, Barclays president Bob Diamond used a high-profile speaking engagement yesterday at Chatham House to reiterate the need to ensure that London's status as one of the world's major financial centres was not harmed by new regulation.