The M4 on the Gloucestershire/Wiltshire border will be closed for two nights next week for barrier installation.

Narrow lanes with 50mph speed restrictions on both carriageways will be in place until the end of March 2015.

The westbound carriageway and the westbound entry slip roads at Junction 17 (Malmesbury/Chippenham) and Junction 18 (Bath/Stroud) will be closed overnight from 9pm on Wednesday, March 25 until 6am the following morning. Diversions will be clearly signposted.

The eastbound carriageway and the eastbound entry slip roads at Junctions 17 and 18 will be closed overnight from 9pm on Friday, March 27 until 6am the following morning. Diversions will be clearly signposted.