A 50 MPH speed limit should be imposed on a busy stretch of the M20 to cut down pollution, it has been claimed.

Maidstone council believes imposing the limit during peak times would also help to keep traffic moving and reduce carbon emissions.

It has made the claim after an air pollution survey in the M20 corridor revealed that nitrogen dioxide levels between junction six, at Sandling, and junction eight, at Bearsted, were unacceptably high.

An air quality management area has also been declared for the entire town to deal with other problem areas such as Fountain Lane at its junction with Tonbridge Road, Barming, Well Road and the Loose Road and Sutton Road junction. All have high levels of nitrogen dioxide, according to the survey.

Cllr Tony Harwood (Lib Dem), cabinet member for the environment, said: "All major towns in the UK face similar problems but Maidstone is going to do something positive to improve its air quality. This designation is an important step towards improving air quality in our town and means that innovative ways to improve air quality will be actively sought, planned for and co-ordinated.

"However, we have got to think about changing behaviour because we can’t go on the way we are going. The amount of traffic on our roads is not sustainable."

Maidstone council does not have the power to alter speed limits but could ask the Highways Agency to consider such a change.

See Friday's Kent Messenger for the full story.