Motorway speed limits are to be cut to 60mph on parts of the network in a trial scheme to cut pollution.
Drivers face £100 fines for breaking the new speed limits plus three penalty points on their licence.
The new limits will be tried out on five mile stretches of the M6 near Birmingham and the M1 at Rotherham, South Yorkshire, from October.
The M602 near Eccles, Greater Manchester and the M5 at Oldbury, West Midlands, will also be affected.
Highways chiefs say the impact of slower moving traffic on roadside air quality will be reviewed in a year’s time. It’s the first time the 70mph speeed limit has been permanently reduced.
The Department for Transport says the trial is among a number of measures to improve air quality by cutting nitrogen dioxide from car exhausts.
Nearly 40,000 premature deaths every year are linked to poor air quality.
Highways England’s Ivan Le Fevre said: “Ultimately the air quality challenge will be solved at the tailpipe by vehicle manufacturers and changes in vehicle use. Until this happens we will continue our extensive programme of pioneering research and solutions.”
