Motorists should prepare for additional overnight lane restrictions on a key crossing this week.

The M4 traveling westbound will be blocked between junction 21 and junction 23, encompassing the Prince of Wales Bridge, from 9pm through 6am to allow for maintenance work on the structure.

An alternate route will be marked along the M48 westbound.

Additional rerouting will impact those traveling on the M49, with northbound traffic instructed to use the M4 eastbound toward junction 20, then transition to the M5 southbound toward junction 16, before connecting back to the M5 northbound, M4 westbound and M48.

Maintenance work on the crossing is underway.