In theory, cities have been at the heart of the government’s plans for economic growth outside London. In reality, the government has tended to focus its attention on the UK’s largest cities like Manchester or Birmingham rather than mid-sized cities. A new report, Key Cities: Unlocking Potential, sets out how involving mid-sized cities like Blackpool and Plymouth more closely in the design and implementation of policy would reap substantial rewards – not just for the government, but for society and the economy as a whole.

A closer look at the June 2016 EU referendum result highlights the value that closer engagement with the UK’s mid-sized cities might bring. While 56% of people in the 10 large core cities voted remain, 60% of the 5.6 million people living in the 20 small and mid-sized key cities comprising the Key Cities group voted leave.

In 2017, a study by the National Centre for Social Research indicated that a sense of exclusion from the political and economic life of the UK strongly influenced the leave vote. The referendum result presents clear evidence that the government needs to engage with mid-sized cities to reconnect with leave-voting communities.

As chair of the Key Cities group, I know that we are well-placed to take on the role as the authentic voice of urban Britain, a voice that would serve as an intermediary between the government and communities that feel left behind by national and global politics.

Newport is among British cities benefitting from recent investment. Photograph: High Level/REX/Shutterstock

Such collaboration may also help meet the ambition of the industrial strategy white paper to boost the UK’s economic productivity, which currently lags 15% behind the G7 average. The 20 Key Cities are already helping to address the UK’s productivity challenge. Bournemouth, for instance, was the No 1 UK city for employment growth in 2017; Sunderland was named Britain’s top exporting city in 2017 by the Centre for Cities; Wakefield has one of the highest housing growth rates in the country; and Southampton, Norwich and Portsmouth are listed in the top 10 UK cities for expected GVA growth.

The UK’s mid-sized cities also have a growing reputation as hotbeds of creativity and innovation. Newport has received significant investment to host a facility to manufacture compound semiconductors, which will drive forward next generation technologies such as driverless cars and 5G, while Wakefield will be home to a new national innovation centre for the creative and digital sector as part of the city’s new five-year plan to boost economic growth.

What more could these cities achieve with greater support, powers, freedoms and flexibilities from the government?

Meanwhile, the pioneering Bradford Pathways model not only seeks to train the city’s young people in the core skills needed for today’s jobs, but also aims to give them the resilience and flexibility needed to take on the jobs of the future.

These examples invite the question: what more could these cities achieve with greater support, powers, freedoms and flexibilities from the government?

A growing body of research demonstrates that mid-sized cities provide enhanced economic and social returns on infrastructure and other investment compared to larger cities. The 20 key cities are worth more than £116bn a year to the UK economy. Raising their collective productivity could, we estimate, enable these 20 places to contribute an additional £214bn to the UK economy over the next decade.

Mid-sized cities are not merely the drivers, but the accelerators of growth. These cities’ economies are agile and ripe for investment, with land available for expansion and a collective population who voted overwhelmingly for Brexit because they believed this would change their lives for the better.

In order to respond effectively to 21st-century post-Brexit economic and social challenges, the government must work with the UK’s mid-sized cities.