Edinburgh is embroiled in a political row as it prepares to hold a referendum on congestion charging. The system would involve two ‘cordons,’ the outer of which would be operational between 7 and 10am. The inner cordon, around the city centre, would be active from 7am to 6.30pm. It would cost £2 to cross either on an inbound journey. Despite considerable organised support, the ‘yes’ campaign is currently trailing in the polls. Edinburgh council has started to offer inducements to boost the ‘yes’ vote, including an hour’s free parking for shoppers. It was also claimed that without the charge pollution would rise to the point that roads would be closed under European regulations. However, it transpired that the pollution was NOx and particulates from buses and taxis. Transport minister Alistair Darling is also pushing Manchester to introduce a charge to help pay for new trams, and wants to use the new ‘tag’ system revealed by Autocar on busy roads.