Construction has started on a £92 million upgrade for the M20.

Months of preparation work has sparked complaints from neighbouring residents and two Kent MPs, who are concerned over noise pollution the smart motorway will bring.

Highways England is upgrading a 6.5 mile stretch of the M20 by adding an extra lane in each direction between junction three for the M26 and junction five for Aylesford.

A 50mph speed limit is currently in place on both carriageways, while overnight lane and carriageway closures will also take place.

Highways England senior project manager, Kam Kaluba, said: "The M20 is a key route connecting people, communities and businesses between London and the Kent coast and upgrading it to a smart motorway will improve the 120,000 journeys it is used for every day.

"Smart motorways create vital extra capacity, give drivers better information and maintain high levels of safety.

"I'd like to thank drivers for their co-operation and understanding while we build this new, improved road."

Work began to clear neighbouring trees and shrubbery in February, which Highways England confirmed it will replace once work is complete.

Noise barriers will be installed between junctions four and five, but MPs Tracey Crouch and Tom Tugendhat have been pushing Highways England to extend the barriers to junction three.

Works will also replace the footbridge crossing the motorway at Teapot Lane in Aylesford.

Replacing the hard shoulder will be five emergency areas and CCTV will cover 100% of the improved motorway.

Work is expected to be complete by January 2020.