Sir, Northern cities need more powers if they are to catch up. Chris Giles and James Wilson are right to highlight the two-speed economy within and between our regions ("A tale of two valleys" and "Gone north", Comment & Analysis, September 19 and 20).

Last week, John Healey, financial secretary to the Treasury, admitted that regional economic differences were proving to be very persistent - and that global trends were set to reinforce the dominance of London and the south-east.

Meanwhile, a recent Organisation for Economic Co-operation and Development report has highlighted the problems facing the north-east economy. The Treasury's own target to reduce regional disparities now looks more challenging than ever.

Our northern regions and cities will be able to catch up only when they have the powers to do so. This calls for a step-change in government. Whitehall needs to let go.

Our regions and city-regions, towns and cities all need much more power and freedom to shape their own economies. If public spending is reduced, increased devolution is likely to improve the efficiency and impact of spend - promoting more effectively targeted spending and levering in additional local resources.

Over the next few months, ministers have the opportunity to push ahead with far-reaching devolution - over transport, skills, planning and local government finance. They should seize this opportunity, starting with the imminent local government white paper.