Drivers are facing delays of around an hour after a collision saw a lorry overturn on a motorway.
National Highways said lanes one and two of the M4 westbound between junction 18 (Bath) and 19 of the M32 are closed and there is approximately four miles of congestion.
According to traffic monitoring website Inrix, traffic was briefly held but lane three has reopened.
National Highways said on social media that traffic has been released after being temporarily stopped to recover the lorry.
The roads agency said: “Lanes one and two remain closed on the M4 westbound between J18 Bath and J19 M32 for recovery of an overturned lorry trailer following a collision.
“There are currently delays of 60 mins and approximately four miles of congestion.”