UPDATED 9.13am: The crash has been cleared, and all lanes are now open.

UPDATED 8.17am: A lane remains blocked eastbound between junctions 23 and 22 of the M4, due to a crash.  

The AA is reporting that it is taking an average of seven minutes for queuing traffic to get past.

ONE lane of the M4 is blocked, eastbound on the Prince of Wales Bridge, and traffic is queuing, because of an incident.

Details are not yet available, but the outside is currently blocked.