The M4 westbound is expected to remain closed until this afternoon following a milk tanker crash.
The motorway is closed between junctions 17 (Chippenham) and 18 (Bath).
Highways England say the ‘complex recovery’ will take several hours to complete, and will involve draining the tanker of its milk before the task of righting the vehicle can begin.
The road also requires emergency resurfacing before it can reopen.
The driver of the lorry escaped the wreckage with minor injuries.