Lib Dems want only ultra low emission vehicles and electric cars from 2040 . Clegg says he wanted to tackle 'dangerous levels of air pollution ' in cities . Launches £100million 'prize ' for firms who build Vince Cable low emission car .
Lib Dems want only ultra low emission vehicles and electric cars from 2040 . Clegg says he wanted to tackle 'dangerous levels of air pollution ' in cities . Launches £100million 'prize ' for firms who build first ultra low emission car .