The Mayor, Boris Johnson, has already called for greater financial autonomy for London, and in particular for the capital to retain any increase from rising stamp duty receipts to spend as City Hall chooses. At present only seven per cent of London’s taxes are retained here for our own needs, far less than, say, New York or Paris. Now Mr Johnson has joined forces with the mayors of other English cities including Birmingham and Manchester to reiterate the call for something like urban devolution. London’s case could be strengthened if other English cities join the call.