I will try to explain how economic geography works to Andy Burnham and Steve Rotheram (Letters, 18 April), and anyone else who would like to know. In relatively small countries, like the UK, economic and other activity becomes attracted to a central city, like London. Under free enterprise conditions, which recent governments purport to be in favour of, it grows and grows, becoming the centre of culture and government as well as business and commerce.

As time passes, the central city develops problems such as high land and labour costs, traffic congestion and pollution. At the same time, new forms of communication make it less necessary for business and other leaders to be in close geographical contact with each other. Eventually, decisions are made to relocate all sorts of economic activities to cheaper, less polluted places, such as Manchester and Liverpool.

In the UK, this has not and will not happen because we invest disproportionately high amounts of money in maintaining London’s advantages – Crossrail being one.

Andy and Steve’s letter tells us that HS2 sites are “drawing up economic plans to take advantage of better connections and released capacity”. I am unsure of the precise meaning of “released capacity” but I do know that by far the best connections will be London’s. HS2 will continue the process of keeping London at the top of the economic pile. The effect on Manchester and Liverpool is more likely to be that of draining their economic lifeblood.

Steve Lupton

Manchester

• As a resident of Greater Manchester, totally opposed to HS2, I read the letter from Andy Burnham and Steve Rotheram with despair and disbelief – words failed me. Alison Leonard’s response (Letters, 19 April) is perfect. As we Quakers say: “That friend speaks my mind.”

Marion McNaughton

Warburton, Greater Manchester

• While being entirely in accord with the sentiments of David Mills and Frank Field concerning the “northern powerhouse”, I would be interested in asking David how one could travel between the centres of Manchester and Leeds without crossing the Pennines.

Martin Pearmain

Huddersfield

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