Speed bumps could be removed from the nation’s roads as part of the Government’s plans to cut pollution.

Other traffic-calming measures could also be removed to prevent cars repeatedly slowing down and speeding up, which almost doubles the amount of harmful gases they pump out.

Councils will be advised to take measures to improve the flow of traffic as part of a new clean air strategy to be unveiled later this month.

Motoring organisations have urged ministers to cut pollution by reducing traffic jams and encouraging drivers to go at a steady speed rather than punishing them with stealth taxes.