'Misguided' Coalition policies for revamping flagging high streets and local authority assistance to out of town business parks are 'hollowing out' many small and medium sized cities, a top economics think-tank has warned.

The Mary Portas review on supporting high street retail and government help for enterprise zones comes at the expense of job-creation which is vital to the prosperity of city centres, the Centre for Cities reports today

Entitled ‘Beyond the high street: why our city centres really matter', it finds that while the centres of the country's largest cities are increasingly magnets for employers, one in three of their smaller counterparts are seeing private sector work relocated to the edge of towns.

Coalition attempts to boost the prosperity of struggling high streets, through the Portas Pilots, is treating the symptom of moribund city centres, and not the cause, which, the paper suggests, is the lack of workers who are likely to spend their money locally.

Report authors argue central government sweeteners in support of Enterprise Zones and local authority subsidy of business parks have also undermined city centre economies, reducing footfall and in so doing harming retailers.