Work to convert a 32 mile stretch of the M4 west of London into a smart motorway is getting underway.

The initial works are beginning between Junction 8/9 (Maidenhead) and 10 (Reading East, A329(M)).  In total the stretch from Junction 4B near the M25 to Junction 12 at Theale will be upgraded.  The work is expected to be completed in 2022.

Highways England says it will also start work on four bridges between Junction 8/9 and Junction 7.  It says the more complex section of the scheme, progressing east from Junction 8/9 towards Junction 3 will be started in May 2019.