London mayor, Boris Johnson, is looking to New York for ideas on improving benefits take-up across the capital, amid ‘scandalous' evidence that poor Whitehall marketing leaves up to £1bn a year in payments unclaimed.

Evidence collated by the Greater London Authority suggests ‘hundreds of thousands' of the capital's low-income residents do not claim the tax credits and other benefits to which they are entitled – cash which could both boost income for vulnerable families and kick-start London's economy through higher consumer spending.