A cross-party group of political leaders from across the country are calling for Government support to tackle air pollution. 14 Mayors and political leaders from London, Manchester, Birmingham, Bristol, Cambridge, Leeds, Leicester, Liverpool, Newcastle, Nottingham, Oxford, Sheffield, Southampton and the West of England Combined Authority have today joined forces to call for the Government to support a network of 30 new and existing Clean Air Zones, where the most polluting vehicles are fined. A report released by UK100, a network of local leaders, shows that towns and cities could see an economic return of £6.5bn with support from the Government to tackle illegal levels of air pollution.