They are actually recommending less growth by 2040 than the modelling by the 3 LEPs report recommends.
Birmingham should be twice the size in order to become a wealthy “global city”, according to a major new report.
That would mean doubling the population to two million people, from around one million today.
And the West Midlands Combined Authority, chaired by mayor Andy Street, should help ensure Birmingham’s population grows by at least 200,000 people by 2040.
Those are some of the findings in a study by think tank Policy Exchange.
Researchers looked at the Government’s Midlands Engine policy, which is supposed to grow the economies of both the West Midlands and the East Midlands, and to encourage the two regions to work more closely together.
One of their findings was that the Midlands would be more successful if Birmingham grows significantly.
The theory is that economies are more productive if there are more people around. This is known as agglomeration.
The Policy Exchange report said: “By locating close together, workers, businesses and families can access a common pool of ideas, skills and people, creating a city that is greater than the sum of its parts.”
If the UK was like most other developed countries then Birmingham would have around two million people, the report said.
Referring to the Organisation for Economic Co-operation and Development (OECD), which includes 36 wealthy countries, the report said: “If Birmingham matched the OECD average for the relative size of a second city, it would be almost twice as large, or around 2 million people.
“By itself, assuming standard agglomeration effects, this might increase productivity by 3-8 per cent, helping close the gap with the South East.
The report said that the UK currently only has one “global city”, which is London, but it could have more.
It said: “Given its population and economy, the UK should be able to support more than one global city.
“In 1950 both Manchester and Birmingham were among the 30 largest cities in the world – today, neither make the top 100 and are rarely brought up in other lists of global power or influence.”
And it said that the West Midlands Combined Authority, the region’s new council which is chaired by the mayor, should help ensure the city grows by at least 20% by 2040, which would mean roughly 200,000 extra people.
Policy Exchange’s Head of Economics and Social Policy Warwick Lightfoot said: “Britain stands out among advanced economies for the poor productivity performance of its second cities. This is not the result of a law of nature. Regional decline has been as much a result of political mistakes as economic destiny.
“The Midlands currently punches below its weight economically – but is fortunate. Unlike some areas of the UK, many of the fundamentals are in its favour, from technological developments in manufacturing to the region’s geography and close connection to London.
“While more needs to be done to address the region’s underlying weaknesses with skills and infrastructure, the reality is that these are secondary to developing world-leading sectors.
“If the Midlands is to substantially close the productivity gap with the rest of the G7, it will have to develop more world leading technologies of its own – and not just be a local base for production.”